How Does Jannik Sinner’s Season Stack Up?

Jannik Sinner, defying gravity

Jannik Sinner just wrapped up a season for the ages. He won both hard-court majors, three Masters 1000s, and the Tour Finals. He led Team Italy to a Davis Cup championship and ended his campaign on a 26-set winning streak.

By November, the Italian was no longer competing against the field: He was gunning for a place in the record books. He went undefeated against players outside the top 20. Not a single player straight-setted him: He won at least one set in each of his 79 matches. Only Roger Federer, in 2005, had ever managed that.

After Sinner won the Australian Open, I wrote that Yes, Jannik Sinner Really Is This Good. Since then, he got even better. In the seven-month span ending in Melbourne, the Italian held 91.1% of his service games, a mark that not only led the tour but put him in the company of some of the greatest servers of all time. For the entire 2024 season, he upped that figure to 91.5%–including thirteen matches on clay.

He also defied the most powerful force in all of sport, regression to the mean. Sinner’s hold percentage was aided by some sterling work saving break points. He won tons of service points, of course, but he was even better facing break point. The average top-50 player is worse: Good returners generate more break points, so it’s a tough trend to defy.

In the 52 weeks ending in Melbourne, Sinner had won three percentage points more break points than overall service points. I wrote then: “I can tell you what usually happens after a season of break-point overperformance: It doesn’t last.” In the Italian’s case, though, it did. In 2024 as a whole, he won 71.1% of service points, and 73.6% of break points. He would have enjoyed a productive season without repeating his break-point overperformance, but those two-and-a-half percentage points explain much of the gap between very good and historically great.

Clubbable

Most players who serve so effectively are middling returners. The Italian has bucked that trend as well.

Late in 2023 I wrote about tennis most exclusive clubs–Alex Gruskin’s method for identifying standout players by their rankings in the hold and break percentage categories. It’s rare for anyone to crack the top ten in both. In 2023, Sinner signaled what was coming by finishing in both top fives. He ranked fifth by hold percentage and fourth by break percentage. Most seasons, that would have been enough for a year-end number one, but Novak Djokovic was even better, finishing in the top three on both sides of the ball.

Sinner, as we’ve seen, served even better this year. His 91.5% hold percentage was well clear of the pack, even with the resurgence of countryman Matteo Berrettini and increased time on tour from rocket men Ben Shelton and Giovanni Mpetshi Perricard. Last season, Djokovic led the tour by holding 88.9% of his service games. That’s impressive, especially for a guy known for other parts of his game, but it wouldn’t have cracked the 2024 top three. The Italian set a new standard.

At the same time, his return barely flagged. He fell out of the the top five by the narrowest of margins, winning nearly as many return games as he did in 2023 but falling to sixth place. Still, a “top-six club” showing is plenty rare. The only players who have posted one since 1991 (when these stats became available) are Djokovic, Nadal, Federer, and Andre Agassi. Federer only managed it once. Sinner has now done it twice.

The Italian’s return skills are even more impressive when we compare him the other season-best servers of the last thirty-plus years. The following table shows the hold-percentage leader for each year, along with his break percentage and his rank (among the ATP top 50) in that category:

Year  Player             Hold%   Brk%  Rank  
1991  Pete Sampras       87.3%  25.4%    40  
1992  Goran Ivanisevic   88.8%  20.4%    48  
1993  Pete Sampras       89.6%  27.7%    19  
1994  Pete Sampras       88.4%  29.3%    19  
1995  Pete Sampras       89.0%  26.0%    25  
1996  Pete Sampras       90.8%  20.8%    43  
1997  Greg Rusedski      91.6%  16.7%    50  
1998  Richard Krajicek   89.2%  21.4%    41  
1999  Pete Sampras       89.7%  21.7%    44  
2000  Pete Sampras       91.7%  18.4%    49  
2001  Andy Roddick       90.4%  19.7%    45  
2002  Greg Rusedski      88.5%  17.6%    48

Year  Player             Hold%   Brk%  Rank    
2003  Andy Roddick       91.5%  20.9%    43  
2004  Joachim Johansson  91.9%  14.5%    48  
2005  Andy Roddick       92.5%  20.8%    45  
2006  Andy Roddick       90.5%  22.4%    43  
2007  Ivo Karlovic       94.5%   9.8%    50  
2008  Andy Roddick       91.2%  19.2%    40  
2009  Ivo Karlovic       92.2%  10.3%    50  
2010  Andy Roddick       91.1%  17.6%    47  
2011  John Isner         90.7%  12.9%    50  
2012  Milos Raonic       92.7%  15.1%    49  
2013  Milos Raonic       91.4%  15.7%    49  
2014  John Isner         93.1%   9.3%    49  

Year  Player             Hold%   Brk%  Rank  
2015  Ivo Karlovic       95.5%   9.6%    50  
2016  John Isner         93.4%  10.9%    49  
2017  John Isner         92.9%   9.6%    50  
2018  John Isner         93.8%   9.4%    50  
2019  John Isner         94.1%   9.7%    49  
2020  Milos Raonic       93.9%  18.0%    44  
2021  John Isner         91.1%   8.8%    50  
2022  Nick Kyrgios       92.9%  19.3%    40  
2023  Novak Djokovic     88.9%  28.8%     3  
2024  Jannik Sinner      91.5%  28.3%     6

If it hadn’t been for Djokovic’s appearance at the top of last year’s list, Sinner’s 2024 campaign would be hardly recognizable. Even Pete Sampras struggled to hold on to a spot in the break-percentage top 20. Circuit-best servers simply aren’t supposed to win so many return games, yet Sinner threatens to make it the new normal.

Carrot yElo

The Italian’s 73 wins, including 18 against the top ten, took his Elo rating to new heights. He began the year with a career-high rating of 2,197, second on the circuit to Djokovic. He quickly took over the top spot, ultimately clearing the 2,300 mark with his victory at the Tour Finals.

Elo is not a perfect measure to compare players from different eras, but in my opinion, it’s the best we’ve got. It’s the basis of my Tennis 128, which Sinner will join as soon as I get around to updating the calculations. 2,300 is rarefied air: In the last half-century, he is only the twelfth player to reach that mark. With three singles victories to secure the Davis Cup, he nudged his rating up to 2,309, surpassing Mats Wilander and establishing the eleventh-highest peak since the formation of the ATP.

A stratospheric Elo is an indication of an outstanding player at the top of his game, but the metric is not designed to rate seasons. The alternative is yElo, a variation I devised for exactly this purpose. yElo works the same way as Elo does, adding or subtracting points based on wins, losses, and the quality of opposition. But unlike the more traditional measure, each player starts the season with a clean slate.

By regular Elo, Sinner holds a 150-point lead over second-place Carlos Alcaraz. By yElo, with its narrower focus, the Italian is even more dominant:

(The won-loss records are a bit different from official figures because my Elo and yElo calculations exclude matches that ended in retirement.)

The two-hundred-point gap between Sinner and Djokovic is one of the largest ever. Again going back to 1973, it ranks fourth. Only 2004 and 2006 Federer (over Lleyton Hewitt and Nadal, respectively) and 1984 John McEnroe (over Wilander) outpaced the competition by such a substantial margin.

By raw yElo, Sinner’s 2024 isn’t quite so historic. It’s the 26th best of the last half-century: An impressive feat, but not as close to the top of the list as some of the other trivia suggests. Here’s the list:

Year  Player              W-L  yElo  
1979  Bjorn Borg         84-5  2499  
1984  John McEnroe       82-3  2476  
2015  Novak Djokovic     82-6  2458  
1985  Ivan Lendl         82-7  2440  
2016  Andy Murray        78-9  2416  
2013  Novak Djokovic     74-9  2408  
1976  Jimmy Connors      97-7  2406  
1977  Bjorn Borg         78-6  2403  
1977  Guillermo Vilas  133-13  2401  
2006  Roger Federer      91-5  2399  
1980  Bjorn Borg         70-5  2395  
1981  Ivan Lendl        96-12  2383  
1987  Ivan Lendl         73-7  2381  
1982  Ivan Lendl        105-9  2380  
1978  Jimmy Connors      66-5  2379  

Year  Player              W-L  yElo  
2013  Rafael Nadal       74-7  2373  
1986  Ivan Lendl         74-6  2369  
2011  Novak Djokovic     63-4  2367  
2005  Roger Federer      80-4  2364  
2014  Novak Djokovic     61-8  2363  
2012  Novak Djokovic    73-12  2360  
1978  Bjorn Borg         79-6  2359  
2008  Rafael Nadal      81-10  2352  
1986  Boris Becker      69-13  2347  
1982  John McEnroe       71-9  2341  
2024  Jannik Sinner      72-6  2339  
1983  Mats Wilander     80-11  2338  
1974  Jimmy Connors      94-5  2332  
1989  Boris Becker       64-8  2329  
2015  Roger Federer     62-11  2329

One factor holding back Jannik’s 2024 is the number of matches played. Elo, in part, reflects the confidence we have in a rating. Winning 90% of 100 matches (or almost 150, in the case of Vilas) gives us more confidence in an assessment than 90% of 80 matches.

Another issue is that Elo has opinions about strong and weak eras. Going 70-5 in 1980 doesn’t look much different than 72-6 today, but Elo considers Bjorn Borg’s peers to have been stronger than Sinner’s. If Sinner and Alcaraz continue to improve and a couple of their peers emerge as superstars in their own right, then a 72-6 season might rank much higher.

The asphalt jungle

A couple of months ago, pundits started mulling where Sinner’s 2024 stood among the greatest hard-court seasons of all time. Since then, he piled on so many more wins that the qualifier wasn’t needed. Yet it remains a valid question.

The Italian’s highlights came almost entirely on hard courts. He won 53 of 56 matches, 42 of them in straight sets. He’s plenty skilled on natural surfaces, but given a predictable bounce and conditions that emphasize his power and penetration, opponents don’t stand a chance.

I don’t publish surface-specific yElo ratings, because they have limited usefulness for much of the year. For our purposes, though, hard-court yElo–same algorithm, limited to matches on one surface–is just the ticket. By this measure, Sinner’s 2024 is the eighth-best of all time:

Year  Player          Hard W-L  Hard yElo  
2015  Novak Djokovic      59-5       2426  
2013  Novak Djokovic      53-5       2413  
2012  Novak Djokovic      48-5       2377  
2005  Roger Federer       49-1       2374  
2006  Roger Federer       59-2       2373  
1995  Andre Agassi        52-3       2370  
2016  Andy Murray         48-6       2363  
2024  Jannik Sinner       52-3       2353  
2010  Roger Federer       45-7       2338  
2014  Novak Djokovic      40-6       2334 

Year  Player          Hard W-L  Hard yElo   
2014  Roger Federer       56-7       2333  
1985  Ivan Lendl          29-3       2332  
1987  Ivan Lendl          33-2       2325  
1996  Pete Sampras        46-4       2319  
2015  Roger Federer       38-6       2318  
1981  Ivan Lendl          41-3       2317  
2011  Roger Federer       45-7       2314  
2009  Novak Djokovic     53-10       2309  
1985  John McEnroe        25-1       2309  
1986  Ivan Lendl          30-2       2298

So, um, peak Djokovic was pretty good, huh?

Even though Elo doesn’t hold the rest of the 2024 field in particularly high regard, Sinner’s season was so dominant that he does well by this measure. A year that would rate as Djokovic’s fourth-best, Federer’s third, or Agassi’s second, is truly something worth celebrating.

The Italian still has some ground to cover before he challenges Novak, Roger, and the rest for all-time hard-court dominance. But he has already upped the standard for the 2020s and posted one of the most remarkable two-year spans in the game’s history. Sinner has built an enormous gap between himself and the field, and it is increasingly difficult to see how his peers will close it.

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Jasmine Paolini’s High-Wire Act

Jasmine Paolini at the 2022 Transylvania Open. Credit: Nuta Lucian

There are unorthodox aging curves, and then there’s whatever the hell Jasmine Paolini is doing right now. The best women tennis players tend to make their presence known in their late teens. I wrote earlier this year about the “improbable rise” of 22-year-old Emma Navarro.

Paolini is 28.

When Paolini was the age that Coco Gauff is now, she was ranked just inside the top 300, fresh off a first-round loss at an ITF $25K in Bulgaria. When she was the age that Iga Swiatek is now, she had finally cracked the top 150, about to head to Wimbledon qualifying. (She lost in the first round there, too.) When she was the age that Aryna Sabalenka is now, she had just stumbled through a four-match losing streak to the likes of Jil Teichmann and Irina-Camelia Begu that knocked her out of the top 50.

Just 16 months ago, Paolini was once again outside the top 50. For a five-foot, four-inch counterpuncher with no obvious weapons, she had achieved a great deal. There was little reason, though, to think she could climb much higher. Her peers were getting bigger, the game was becoming ever more aggressive, and she was reaching the age at which WTA stars begin to think about what else life might hold for them.

Then she started winning.

Since leaving Wimbledon last year, the Italian has won 66 of 99 matches, including two major semi-finals and five top-ten scalps. She picked up her first 1000-level title and made four other finals. Yesterday, she led Team Italy to a Billie Jean King Cup crown, starring in both singles and doubles en route to the championship. Her ranking is up to an astonishing 4th in the world. As if that weren’t enough, she’s in the top ten in doubles.

None of this was supposed to happen. Paolini’s late-2023 surge to the top 30 was one thing; what has happened since simply defies belief. How has she managed it? Is it a fluke, or will we see the Italian at the 2025 year-end championships as well?

Opportunistic effects

First, a bit of a caveat. Paolini, like Taylor Fritz, has played the official ranking system like a Stradivarius. She reached only three finals in 2024, yet two of them were slams. The other was a 1000. She earned huge chunks of points for a semi-final defeat of Mirra Andreeva at Roland Garros, a semi-final squeaker against Donna Vekic at Wimbledon, and a Dubai title that didn’t require her to face a top-ten opponent.

None of this is meant to take away from Paolini’s accomplishment. She beat the players in front of her, and in the case of Andreeva, she did so in emphatic fashion. The point is that her top-four finish has more to do with good timing than consistently dominant play.

My Elo ratings offer a second opinion, using an algorithm based on the quality of her opponents, rather than the venue and round of each match. By Elo, she stands in 9th place, just ahead of Madison Keys and Diana Shnaider, well back of Jessica Pegula and Elena Rybakina. Still a very good season, if a bit less astounding.

Even more revisionist is the total-points-won leaderboard. Going into the BJK Cup Finals, Paolini had won 51.8% of her total points this season. That’s a respectable rate, especially for someone who hovered in the 50% range for most of her tour-level career. But it is not typically top-five, or even top-ten material:

By this metric, the Italian stands in 19th place among the WTA top 50, behind a handful of players who didn’t even crack the official top 20. That doesn’t really mean she’s the 19th best player on tour: She faced one of the toughest schedules of anyone. Much as I love both Yulia Putintseva and counterintuitive arguments, I’m not going to try to convince you that Putintseva had the better season.

Still, Paolini’s position on the TPW list tells us something about how she won her matches. She didn’t lose many blowouts, but she didn’t win many, either. (She certainly didn’t get in the habit of spanking opponents like Swiatek and Sabalenka do.) Ten of her wins required a third set. Two victories–including the Wimbledon semi-final–came despite losing more points than she won.

The margins were not so narrow that we can ascribe the Italian’s breakout to luck. (Though the Vekic match could have gone either way, to say the least.) But this is the high-wire act that took Paolini to the top. She doesn’t have the tools to bludgeon her opponents. She has done a lot of things right to win 42 matches this year. To keep winning at a two-of-three clip, she’ll need to continue executing the new game plan to near-perfection.

The new game plan

It’s a bit tricky to isolate the key changes in Paolini’s approach, because–like Qinwen Zheng–she’s doing almost everything better than she did before the surge. That said, a few things stand out.

Check out the Italian’s breakdown of points won by rally length (in Match Charting Project-logged matches) before this season, compared with her performance this year:

Span     1-3 W%  4-6 W%  7-9 W%  10+ W%  
2016-23   49.1%   46.5%   51.0%   49.4%  
2024      49.8%   54.3%   56.6%   49.1% 

Paolini’s improvement in 7- to 9-stroke rallies is significant, and her gain in the 4- to 6-shot category is enormous. In very short points and very long ones, little has changed.

Especially in the categories of shorter points, we need to keep in mind what these win rates measure. It’s tempting to think of a prototypical short point, then imagine Paolini, instead of her opponent, winning it. But the length of a given point is not handed down to us by God. When someone like Paolini starts winning more shorter points, it’s because she is ending them before they become long points, and/or she is preventing her opponents from ending points quickly.

The Italian can hardly stack up one-shot points (unreturned serves), and she can’t even reliably put away plus-ones–though she is doing that more than she used to. Instead, like the expert doubles player she has become, she can structure points that inch closer and closer to a point-ending opportunity. Call it plus-two tennis, aggressive point construction for undersized counterpunchers.

The plus-two forehand

Tactics are one thing; Paolini is a top-ten player because she has executed them so well. Her forehand is a big reason why.

She is ending points with her forehand at a much better clip than she did before the calendar flipped to 2024, and her inside-out forehand has seen particular improvement:

Span     FH Wnr%  DTL Wnr%  IO Wnr%  FHP/100  
2016-23    11.7%     17.7%     6.2%      2.9  
2024       17.5%     25.2%    13.3%     10.2

Here, “winners” refer to both clean winners and shots that induce forced errors. Through 2023, Paolini’s forehand winner/forced error rate of less than 12% put her in the bottom quarter of tour regulars. 17.5% moves her to the top third, not far behind Swiatek and Keys. The same stat for inside-out forehands (IO Wnr%) doesn’t put her in quite the same company, but it is an even better reflection of the tactical shift. Before, the Italian rarely used that shot as an offensive weapon; now it is a regular part of the arsenal.

The bottom line is reflected in the Forehand Potency (FHP/100) numbers. The number of points Paolini earns with her forehand more than tripled from previous seasons to 2024. That doesn’t quite account for the entire shift from a top-50 player to a top-fiver, but it explains a whole lot.

And the no-fearhand

One side effect of the Italian’s forehand-centered strategy is that she is less afraid of other players’ forehands.

Again, Paolini is doing just about everything better. For instance, 22% of her first serves went unreturned in 2024, compared with 20% in the past. Nice little boost, but not something you would notice by watching a couple of matches. A bigger shift is where she puts the first serves:

Span     1st Unret%  <=3 W%  RiP W%  D Wide%  A Wide%  
2016-23       20.2%   28.1%   48.3%    25.0%    45.7%  
2024          21.8%   34.8%   53.4%    37.4%    44.8%

Check out the rate at which she is hitting deuce-court first serves wide (D Wide%). 25% to 37% is a massive change, and one that would be dangerous for a different sort of player. In the deuce court, the down-the-tee serve is the conservative one: It goes to the backhand of a right-handed returner, and since it lands in the middle of the court, the returner doesn't have any sharp angles to exploit. The wide serve is the opposite, feeding forehands to opponents like Sabalenka, Rybakina, or Zheng along with the angles necessary to turn them into winners.

What Paolini knows--again, like a savvy doubles player--is that most players will fail to convert the majority of those opportunities, even if they occasionally smack a highlight-reel return winner. The Italian didn't crack the top five by running the table against the elite. Most of her 42 wins came against the next rung of competitors, women who are often held back by inconsistency. Paolini pushed them off the court, giving the choice of either going big (and frequently missing), or sending back a shot that she could handle with her own (improved!) forehand.

All those deuce-court wide serves explain how Paolini picked up so many more plus-one winners (the <=3 W% column) and converted so many in-play returns overall (RiP W%). Every individual wide serve is a gamble, but the Italian has discovered that, on net, they pay off.

The way forward

I'm a bit surprised to find myself concluding that, yes, Paolini might just maintain this level. The odds are heavily against another top-five finish. That was a quirk of her draws and well-timed (probably accidental!) peaks. But 52% of total points? A single-digit year-end ranking? Maybe!

Once I began thinking of the Italian's singles play in terms of doubles strategy, it all clicked. Her anticipation is outstanding--and like everything else, it is better than it was last year. She often wins points without working particularly hard. She's in the right place to end the point on the fifth or sixth shot of the rally. (That place is increasingly at the net. She came to net more in 2024, and she won more of those points than before, too.) Anticipation isn't a skill that will deteriorate with age, nor is it one that opponents can neutralize.

Paolini's new point-shortening, forehand-smacking, deuce-court-serving tactics aren't going to earn her many big upsets, just as they haven't so far. The strongest players--not coincidentally, often the ones with the most fearsome forehands--are the ones in the best position to take advantage the wide deuce-court serves and force the Italian both to move off the baseline and rely more on the backhand.

But a top-ten season doesn't require a pile of top-ten victories. Paolini was 3-6 against that group this year, and that included one win against a fading Ons Jabeur and another in Riyadh against a rusty Rybakina. The Italian's finish owed much more to her 38-15 record against everyone else. Despite the improbability of a top-ten debut at age 28, Paolini has built a game capable of repeating the feat in 2025.

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The Newly Opportunistic Taylor Fritz

Taylor Fritz at the 2023 US Open. Credit: Andy M. Wang

Taylor Fritz has been remarkably consistent over the last three seasons. He ended the 2022 campaign ranked 9th, finished last year 10th, and enters this week’s Tour Finals in 5th place, with a chance to overtake Daniil Medvedev for a spot in the top four.

Take a look at his top-line statistics for 2022, 2023, and 2024. They’re sorted by total points won (TPW). Can you tell which one belongs to his career-best current season?

Year   Win%   1st%   2nd%    RPW    TPW  
???   68.8%  78.4%  54.3%  37.7%  53.0%  
???   70.4%  78.3%  55.8%  36.2%  52.8%  
???   69.1%  76.4%  52.6%  38.2%  52.4%

You might be tempted to go with the first row, since he won the most points then. But the margin is small, and he won matches at a better clip in the second. Wait, though: He snagged the most return points in the third season, and more breaks of serve are particularly crucial for a player hovering in the 36% to 38% range.

I won’t leave you hanging. The second line belongs to 2024. Here are the three stat lines, now sorted by season:

Year   Win%   1st%   2nd%    RPW    TPW  
2024  70.4%  78.3%  55.8%  36.2%  52.8%  
2023  68.8%  78.4%  54.3%  37.7%  53.0%  
2022  69.1%  76.4%  52.6%  38.2%  52.4% 

The 27-year-old American is clearly doing something right that isn’t captured by the usual stats. 10th to 5th is a major move. Last year he didn’t even qualify for the Tour Finals. After beating Medvedev yesterday, he’s one win away from a probable berth in the semis. What’s going on here?

All the right matches

The official ranking system ensures that tournaments and matches are very much unequal. When Fritz beat Frances Tiafoe in the Acapulco quarter-finals last year, he gained an additional 90 points for his semi-final showing. When he slipped past Tiafoe in this year’s US Open for a place in the championship match, he earned a whopping 480 points.

I could just about stop here. 480 points is the difference between Fritz’s current point total and 8th place. A slightly bigger difference of 560 points would knock him down to 10th, and he’d be hanging around Turin this week as an alternate. His stats would barely change, but the story of his season would be very different.

It’s not just the Tiafoe match; it’s more than the US Open final. 2024 was the first year that Fritz lived up to expectations at the slams in general. Here are his grand-slam win totals back to 2018:

Year  Wins                  
2024    17                  
2023     8                  
2022     8                  
2021     6                  
2020     6  * no Wimbledon  
2019     4                  
2018     4

No top tenner would be happy with just eight wins at majors. Simply reaching the fourth round at each slam adds up to 12. In 2022, Fritz lost five-setters to Stefanos Tsitsipas and Rafael Nadal, then fell to a streaking Brandon Holt in Flushing. Last year, he suffered two second-round exits. Both five-setters, the losses came against Alexei Popyrin in Australia and Mikael Ymer at Wimbledon.

When the 2024 season kicked off, Fritz had just two major quarter-finals to his name. His career record in five-setters was 8-10.

Since then, the American has reached three more quarters (including the US Open final run). He won four five-setters against just one defeat. He avenged the Melbourne loss to Tsitsipas and twice upset Alexander Zverev, a player who had beaten him in five of eight previous meetings.

The re-balancing

The odd thing about Fritz’s season is that his slam success has been offset by weaker results elsewhere. Returning to the observation I started with: He won nine more matches at majors in 2024 than in 2023, but his winning percentage barely budged. Instead of losing to Ymer or Holt on a big stage, he fell to Matteo Arnaldi in Acapulco, Thiago Seyboth Wild in Miami, Alex Michelsen in Geneva, and more.

It was a smart trade, though it was surely not a premeditated one. You can train with the majors in mind, but you can hardly punt an early-round match at a 250 with any kind of hope that it will result in a quarter-final victory at the next slam.

There’s another category, though, in which Fritz may have used stronger tactics to get better “luck.” Here are the American’s tiebreak records since 2021:

Year  TB W-L    TB%  
2024   21-11  65.6%  
2023   25-17  59.5%  
2022   24-20  54.5%  
2021   20-15  57.1%

The 2023 mark of 59% is about where Fritz should be, based on the rate at which he normally wins serve and return points, combined with the matches in which he finds himself in tiebreaks. 2024 was the first season he beat tiebreak expectations by a non-negligible margin.

This could be luck. Tiebreak records fluctuate, and very few players sustain records above or below expectations for long. Still, the American might have figured something out. In the sample of 2024 matches logged by the Match Charting Project (plus several others from grand slams), Fritz is serving way better in tiebreaks than he has in the past:

Year  TB SPW  
2024   80.3%  
2023   65.6%  
2022   70.9%  
2021   65.0% 

80% is Isner territory. In the improbable event that Fritz can sustain these kinds of numbers, coupled with a solid return-points-won rate around 38%, he should be winning even more tiebreaks than he already does.

I don’t want to overemphasize tiebreaks: After all, his 21-11 record is only one or two tiebreaks better than it “should” be. On the other hand, it’s easy to scan through Fritz’s career results–including those at majors–and see how one or two tiebreaks could change the story. He took a first-set tiebreak from Tsitsipas in Melbourne this year. He split two against Zverev at Wimbledon, then took two of two from the German in New York. Take one of those away–just one!–and again, he might be watching the Tour Finals from the sidelines.

Zverev tolerance

Regardless of whether tiebreak luck played a role, Fritz’s two major victories over Zverev helped to define his season. Neither pre-match betting odds nor my Elo ratings predicted an American victory on either occasion.

Both Fritz and Zverev are tall guys with big serves; either one can put away a service game with four quick strikes. One key difference between them is that Zverev is more patient, comfortable playing long points from the baseline. This isn’t necessarily an asset: It isn’t always in the German’s interest to let matches go that way. But if you’re going to pick one of these two guys to play points from the baseline, it’s pretty clearly Zverev.

In the US Open quarter-final, though, 39 points went ten strokes or longer. Fritz won 20 of them. In the fourth-set tiebreak, three and half hours into the battle, the American won two of two: a 24-stroke grinder that Fritz finished at the net, then a 12-shotter on match point that Zverev squandered with a unforced forehand error.

Two lessons jump out. First, the American can hold his own from the backcourt with one of the best baseliners in the game, at least on a hard court. Second, that skill doesn’t seem to fade with fatigue, something that might have caused Fritz’s five-set struggles in the past.

A third takeaway may be even more important. Instead of the numerator–20 points won–consider the denominator: 39 points played. The first time Fritz and Zverev met at a major, at Wimbledon back in 2018, barely half as many points lasted so long, even though the match itself was longer. Yes, the surface kept that number down, but not by a factor of two. At Washington early in Fritz’s career, on a surface more like that in Flushing, the two men played an entire match with just one rally that reached ten strokes.

In that 2018 Wimbledon meeting, Fritz held his own in the long rallies, winning 9 of 21. The problem was his rush to avoid them. He committed 56 unforced errors to the German’s 36.

Zverev keeps his unforced error rates down because he is willing to wait. He forces opponents to take risks unless they want to spend all day grinding out baseline battles. Most players in the Fritz mold–including Fritz himself, in the past–opt to take their chances. They usually lose, which is why Zverev is ranked second in the world. The American has steadily improved his groundstrokes and his fitness to the point that he doesn’t need to take low-percentage big swings. It’s no guarantee of victory–after all, Fritz won just 50.9% of points in the Flushing four-setter–but it’s a better bet than the alternative.

Let’s play ten

There’s a wider lesson here, and not just for Taylor Fritz. We tend to think of long-rally proficiency as a clear-cut skill. Yes, some players are better at it than others, but not by a wide margin.

Here are the long-rally (10+ shots) winning percentages for the ATP top ten, based on Match Charting Project data for the last 52 weeks:

Player            10+ W%  
Alex de Minaur     57.4%  
Carlos Alcaraz     57.1%  
Jannik Sinner      55.8%  
Daniil Medvedev    55.0%  
Grigor Dimitrov    54.2%  
Novak Djokovic     52.8%  
Andrey Rublev      51.8%  
Casper Ruud        50.2%  
Alexander Zverev   50.2%  
Taylor Fritz       46.8% 

Before I studied this, I would’ve expected considerably more dispersion. While every edge counts, this one is not as crucial as it gets credit for. Fewer than one in ten points reach the long-rally threshold, so even the most extreme gaps–like that between Fritz and de Minaur here–would determine the outcome of only the closest matches.

More important, I suspect, is willingness to play these points. Fritz is never going to crack the top half of a list like this. He has–to his credit–maxed out the rally tolerance that his size and physical gifts will grant him. Still, a 47% chance of winning a protracted point is better than his odds after belting a low-percentage salvo to avoid the battle altogether.

Players who serve as effectively as Fritz does tend to be considerably less sturdy from the baseline. Pros with his (adequate if not world-beating) groundstrokes are often less inclined to rely on them. One-dimensional big servers almost never reach the top five. Yet Fritz, combining his primary weapon with a tactical savvy that allows him to maximize the rest of his assets, has done exactly that.

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Elena Rybakina and the Value of Average

Also today: Ugo Humbert in the (Elo) top ten; South American Davis Cup hard courts

Elena Rybakina at the 2023 US Open. Credit: Hameltion

Never underestimate average. Establishing oneself on the top level of the pro tennis circuit is extraordinarily difficult; proving that any particular skill is average among one’s tour-level peers is even harder. Most players are better than the norm in some categories, worse in others. Anyone who can beat the middle of the pack in every department is virtually guaranteed to be a superstar.

Average is Elena Rybakina’s secret weapon. You probably didn’t know she needed one, because she has a very effective, very evident non-secret weapon: an unreadable bullet of a first serve. In the last year, over 43% of her first serves have gone unreturned. No one else on tour comes within three percentage points of that, and only five other women top 35%. On a good day, the serve can put a match out of reach nearly on its own. When she faced Aryna Sabalenka in Beijing last fall, 65% of her first serves didn’t come back. Most women barely manage to win that many first serve points, let alone decide them with one stroke.

I’ll come back to the serve in a moment, because it is so remarkable, and it would be strange to talk about Rybakina without discussing it. But what makes her a contender every week–not to mention a champion in Abu Dhabi yesterday–is the way that the rest of her game doesn’t hold her back. Among the other women who end points with more than 35% of their first serves, you’ll find a long list of weaknesses. Qinwen Zheng doesn’t put nearly enough of them in the box. Donna Vekic and Caroline Garcia struggle to break serve. Liudmila Samsonova doesn’t break much, either, and her mistakes come in excruciating, match-endangering bunches.

Lopsided player profiles make sense. Only a few people have the combination of natural gifts and discipline to develop a dominant serve. Tennis skills are correlated, but not perfectly so. Someone who serves like Vekic can often learn good-enough groundstrokes and secondary shots. But players with one standout skill are unlikely to be solid across the board. Just because someone is top ten in the world in one category, why would we expect them to rank in the top 100 by a different measure?

Rybakina has reached the top–or close, anyway–by coupling a world-class serve with a set of skills that lacks defects. (You can nitpick her footwork or technique, but none of that holds her back when it comes to winning enough points.) After we review the devastation wrought by her serve, we’ll see just how average she otherwise is, and why that wins her so many matches.

First serves first

I’ve already given you the headline number: Since this time last year, 43.4% of Rybakina’s first serves haven’t come back. That’s one percentage point better than Serena Williams’s career rate. Serena’s numbers are based on matches logged by the Match Charting Project, a non-random sample skewed toward high-profile contests against strong opponents, so I’m not ready to say outright that Rybakina is serving better than Serena. But I’m not not saying that–we’re within the margin of error.

Some back-of-the-envelope math shows what kind of gains a player can reap from the best first serve in the game. Rybakina makes about 60% of her first serves–lower than average, but probably worth the trade-off. (And improving–we’ll talk about that in a bit.) When the serve does come back, she wins about half of points, roughly typical for tour players. All told, 43% of her serve points are first-serve points won. Tack on about half of her second serve points–she wins 48% of those, better than average but not by a wide margin–and we end up with her win rate of 62.5% of serve points–fourth-best on tour.

Put another way: We combine one world-class number (unreturned first serves) with a below-average figure (first serves in), one average number (success rate when the serve come back), and one more that was slightly better than average (second-serve points won). The result is an overall success rate that trails only those of Iga Swiatek, Sabalenka, and Garcia. That, in case you ever doubted the value of an untouchable first serve, is the impact of one very good number.

The key to Rybakina’s first serve–apart from blinding speed–is its unreadability. She must lead the tour in fewest returner steps per ace, a stat I dreamed up while watching the Abu Dhabi semi-final on Saturday. Samsonova seemed to stand bolted to the ground, watching one serve after another dart past her. After one business-as-usual ace out wide, Samsonova even offered a little racket-clap of appreciation, an unusual gesture for such a routine occurrence.

In addition to the deceptiveness of a nearly identical toss and service motion, Rybakina is effective in every direction. There’s no way for an opponent to cheat to one side, hoping to get an edge on a delivery in that corner of the box. Here are Elena’s rates of unreturned first serves and total points won in each corner of the two service boxes:

Direction   Unret%  Won%  
Deuce-Wide     36%   69%  
Deuce-T        45%   75%  
Ad-T           37%   70%  
Ad-Wide        42%   74%

The average player ends points with their first serve between 20% and 25% of the time and wins 60% of their first serve points. Rybakina obliterates those numbers in every direction. If there’s a strategy to be exploited, it’s that returners ought to lean toward their forehand, because if the serve comes to their backhand, they don’t have a chance anyway.

The scariest thing for the rest of the tour is that the 24-year-old’s biggest weapon may be getting even bigger. Her 43.4% rate of unreturned first serves in the last 52 weeks compares favorably to a career clip of 38.2%. Against Samsonova on Saturday, over 41% of all serves didn’t come back, better than Rybakina managed in any of their four previous meetings.

She may be getting savvier, too. One of the dangers of a game built around a single weapon is that certain players might be able to neutralize it. Daria Kasatkina, Elena’s opponent in yesterday’s final, is just such an opponent, a resourceful defender and a first-class mover. When the two women played a three-and-a-half-hour epic in Montreal last summer, Kasatkina put three-quarters of first serves back in play, something that few women on tour could manage and one of the main reasons the match stretched so long. Rybakina survived, but she was broken ten times.

Yesterday, Kasatkina was as pesky as ever, getting almost as many balls back as she did in Montreal. But Rybakina took fewer chances with her first strike, perhaps as much to counter the wind as to adjust for her opponent. Whatever the reason, Elena made three-quarters of her first serves. She had never landed more than 61% against Kasatkina.

The Abu Dhabi final was an exaggerated example of a longer-term trend. Somehow, Rybakina is making way more first serves than ever before, sacrificing no aces and only a fraction of first-serve points won. The overall results speak for themselves:

Year    1stIn%  1st W%   Ace%   SPW%  
2024     66.8%   70.9%  10.3%  64.8%  
2023     56.8%   73.6%  10.5%  62.8%  
Career   57.8%   71.1%   8.4%  62.0%

It’s not a perfect comparison, because the entire 2024 season so far has been on hard courts. Her season stats will probably come down. But a ten-percentage-point increase in first serves in? Nobody does that. Kasatkina won just five games yesterday, and she won’t be the last opponent to discover that whatever edge she once had against Rybakina is gone.

Average ballast

As Ivo Karlovic can tell you, the best service in the world can take you only so far. Some first serves will go astray, some serves will come back, and then there’s the whole return game to contend with. Women’s tennis rarely features characters quite as one-sided as Ivo, but Vekic and Garcia illustrate the point, struggling to string together victories because their serves alone are not enough.

Here’s a quick overview of how the rest of Rybakina’s game stacks up against the average top-50 player over the last 52 weeks:

Stat     Top-50  Elena  
2nd W%    46.7%  48.4%  
DF%        5.2%   3.9%  
RPW       44.4%  44.2%  
Break%    35.5%  36.9%  
BPConv%   46.6%  43.5%

She’s somewhat better than average behind her second serve, as you’d expect from someone with such a dominant first serve. It’s aided by fewer double faults than the norm. On return, we have two separate stories. Taking all return points as a whole, Rybakina is almost exactly average, matching the likes of Barbora Krejcikova and Marta Kostyuk. The only category where she trails the majority of the pack is in break point conversions–and by extension, breaks of serve.

The discrepancy between Rybakina’s results on break points and on return points in general may just be a temporary blip. Most players win more break points than their typical return performance, because break points are more likely to arise against weaker servers. That hasn’t been the case for Elena in the last 52 weeks, and it wasn’t in 2022, either, when she won 41.9% of return points that year but converted only 40.5% of break opportunities.

Match Charting Project data indicates that she is slightly more effective returning in the deuce court than the ad court; since most break points are in the ad court, that could explain a bit of the gap. Charting data also suggests she is a bit more conservative on break point, scoring fewer winners and forced errors than her normal rate, though not fewer than the typical tour player. It may be that Rybakina will always modestly underperform on break opportunities, but it would be unusual for a player to sustain such a large gap.

In any case, she hasn’t struggled in that department in 2024. In 13 matches, she has won 46.9% of return points overall and 47.3% of break points. It’s dangerous to extrapolate too much from a small sample, especially on her preferred surface, but it may be that Rybakina’s single weak point is already back to the top-50 norm of her overall return performance.

The value of all this average is this: What Rybakina takes with her first serve, she doesn’t give back with the rest of her game. We’ve already seen how a standout rate of unreturned first serves–plus a bunch of average-level support from her second serve and ground game–translates into elite overall results on serve. A tour-average return game generates about four breaks per match. Elena has been closer to 3.5, but either way, that’s more than enough when coupled with such a steady performance on the other side of the ball.

I can’t help but think of Rybakina’s “other” skills as analogous to the supporting cast in team sports. Her first serve is an all-star quarterback or big-hitting shortstop; the rest of her game is equivalent to the roster around them. In baseball, a league-average player is worth eight figures a year. Though Elena’s return, for instance, doesn’t cash in to quite the same degree, it is critical in the same way. A superstar baseball player can easily end up on a losing team, just as Caroline Garcia can drop out of the top 50 despite her serve. Rybakina is at no risk of that.

A final striking attribute of Rybakina’s game is that her array of tour-average skills can neutralize such a range of opponents. Her weekend in Abu Dhabi was a perfect illustration, as she overcame Samsonova and Kasatkina, two very different opponents, each of whom has bedeviled her in the past. Elena is more aggressive than the average player, but she is considerably more careful than Samsonova; her Rally Aggression Score is equivalent to Swiatek’s. She was able to take advantage of the Russian’s rough patches without losing her own rhythm or coughing up too many errors of her own.

Against Kasatkina, she posted the most unexpected “average” stat of all. In a matchup of power against defense, defense should improve its odds as the rallies get longer. On Sunday, the two women played 15 points of ten strokes or more, and Rybakina won 8 of them. In her career, Elena has won 52% of those points–probably more by wearing down opponents with down-the-middle howitzers than any kind of clever point construction, but effective regardless of the means.

Rybakina won’t beat you at your own game. But she’ll play it pretty well. Combined with the best first serve in women’s tennis, drawing even on the rest is a near-guarantee of victory. Abu Dhabi marked her seventh tour-level title, and it will be far from her last.

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Ugo Humbert, Elo top-tenner

You probably don’t think of Ugo Humbert as a top-ten player, if you think of him at all. The 25-year-old left-hander cracked the ATP top 20 only a few months ago, and his title last week in Marseille gave him a modest boost to #18.

Elo is much more positive about the Frenchman. Today’s new Elo rankings place him 9th overall, just behind Hubert Hurkacz, the man he defeated to reach the Marseille final. Humbert has always been dangerous against the best, with a 22-25 career record facing the top 20, and a 10-12 mark against the top ten.

Humbert’s place in the Elo top ten might feel like a fluke; there’s a tightly-packed group between Hurkacz at #8 and Holger Rune at #13, and an early loss in Rotterdam could knock the Frenchman back out of the club. But historically, if a player reaches the Elo top ten, a spot in the official ATP top ten is likely in the offing.

I wrote about this relationship back in 2018, after Daniil Medvedev won in Tokyo. As his ATP ranking rose to #22, he leapt to #8 on the Elo list. In retrospect, it’s odd to think that “Daniil Medvedev will one day crack the top ten” was a big call, and it wasn’t that far-fetched: Plenty of people would’ve concurred with Elo on that one. He made it, of course, officially joining the elite the following July.

In that post, I called Elo a “leading indicator,” since most players reach the Elo top ten before the ATP computer renders the same judgment. This makes sense: Elo attempts to measure a player’s level right now, while the ATP formula generates an average of performances over the last 52 weeks. That’s a better estimate of how the player was doing six months ago. Indeed, for those players who cracked both top tens, Elo got there, on average, 32 weeks sooner. In Medvedev’s case, it was 40 weeks.

Most importantly for Humbert, Elo is almost always right. In October 2018, I identified just 19 players who had reached the Elo top ten but not the ATP top ten. Three of those–Medvedev, Stefanos Tsitsipas, and Roberto Bautista Agut–have since taken themselves off the list. One more has come along in the meantime: Sebastian Korda joined the Elo top ten in early 2023, but his ATP points total has yet to merit the same ranking.

Most of the Elo-but-not-ATP top-tenners had very brief stays among the Elo elite: Robby Ginepri qualified for just one week. The only exception is Nick Kyrgios, who spent more than a year in the Elo top ten, thanks to his handful of victories over the best players in the game. His upsets earned him plenty of notoriety, but his inability to consistently beat the rest of the field kept his points total deflated.

Humbert, in his much quieter way, fits the same profile. His serve means that he can keep things close against higher-ranked players, but he has struggled to string together enough routine wins to earn more of those chances. (Injuries haven’t helped.) Still, the odds are in his favor. In 32 weeks–give or take a lot of weeks–he could find himself in the ATP top ten.

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Surfaces in South American Davis Cup

It dawned on me about halfway through the deciding rubber of the Chile-Peru Davis Cup qualifying tie: They were playing on a hard court! In South America! Against another South American side!

It made sense for Chile, with big hitters Nicolas Jarry and Alejandro Tabilo leading the team, and they did indeed vanquish the Peruvian visitors. But South America is known as a land of clay courts, the home of the “Golden Swing.” It seemed weird that an all-South American tie would be played on anything else.

As it turns out, it isn’t that unusual. Since the late 1950s, I found 252 Davis Cup ties between South American sides. I don’t have surface for 37 of them, almost all from the 1970s. Presumably most of those were on clay, but since that’s the question I’m trying to answer, I’m not going to assume either way.

That leaves us with 215 known-surface ties, from 1961 to the Chile-Peru meeting last weekend. (I’m excluding the matchup between Argentina and Chile at the 2019 Davis Cup Finals, since neither side had any say in the surface.) To my surprise, 37 of those ties–about one in six–took place on something other than clay. That’s mostly hard courts, but five of them were played on indoor carpet as well.

The country most likely to bust the stereotype has been Venezuela, which preferred hard courts as early as the 1960s. Ecuador also opted to skip clay with some frequency; it accounted for the first appearance of carpet in an all-South American tie back in 1979.

Chile has generally stuck with clay, but not always. The last time they hosted a South American side on another surface was 2000, when they faced Argentina on an indoor hard court. The surface probably wouldn’t have mattered, as Marcelo Rios and Nicolas Massu were heavy favorites against a much weaker Argentinian side. Though they won, the home crowd was so disruptive that the visitors pulled out without playing the doubles. Chile was disqualified from the next round and barred from hosting again until 2002.

The crowd last weekend was typically rowdy, but Jarry and Tabilo advanced without controversy. For some South American sides, hosting on hard courts may finally become the rule, not the exception.

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What Is Going Wrong For Novak Djokovic?

Also: Arina Rodionova (probably) in the top 100

Novak Djokovic practicing at the 2023 US Open. Credit: Amaury Laporte

Fifteen break points. A week has passed, a new champion has been crowned, and I still can’t stop thinking about it. In the first two sets of his Australian Open quarter-final match against Taylor Fritz, Novak Djokovic failed to convert fifteen straight break points.

It’s so far out of character as to defy belief. Djokovic has converted more than 40% of his break chances in the past year, even counting the 4-for-21 showing in the entire Fritz match. The American, one of the better servers on tour, typically saves only two-thirds of the break points he faces. The chances that Novak would come up short 15 times in a row are about one in seven million.

Even stranger, it wasn’t because Fritz served so well. He missed his first serve on 7 of the 15 break points. He hit two aces and another four didn’t come back, but that leaves nine rallies when–under pressure, in Australia–Taylor Fritz beat Novak Djokovic. Five of those lasted at least seven strokes, including a 25-shot gutbuster at 4-3 in the second set that was followed, two points later, by yet another Fritz winner on the 17th shot. All credit to the American, who walked a tightrope of down-the-line backhands and refused to give in to an opponent who, even in the first two sets, was outplaying him. But clearly this wasn’t a matter of Fritz intimidating or otherwise imposing himself on Novak.

There’s no shortage of explanations. Djokovic is recovering from a wrist injury that hampered him in his United Cup loss to Alex de Minaur. He apparently had the flu going into the Melbourne semi against Jannik Sinner. The whole Australian adventure might be nothing more than a health-marred aberration; in this interpretation, none of Jiri Lehecka, Dino Prizmic, Alexei Popyrin, or even Fritz would otherwise have taken a set from the all-time great.

But… the man is 36 years old. If other tennis players his age are any guide, he may never be fully healthy again. He will continue to get slower, if only marginally so. He personally raised the physical demands of the sport, and finally, a younger generation has accepted the challenge. Djokovic has defied the odds to stay on top for as long as he has, but eventually he will fade, even if that means only a gentle tumble out of the top three. After a month like this, we have to ask, is it the beginning of the end?

Rally intolerance

The two marathon break points that Fritz saved were not exceptions. 64 of the 269 points in the quarter-final reached a seventh shot, and the American won more than half of them. Even among double-digit rallies, the results were roughly even.

Here’s another data point: Djokovic fought out 53 points in his first-rounder against Prizmic that reached ten shots or more. The 18-year-old Croatian won 30 of them. Yeah, Prizmic is a rising star with mountains of potential, but he’s also ranked 169th in the world. This is not the Novak we’ve learned to expect: Even after retooling his game around a bigger serve and shorter points, he remained unshakeable from the baseline, his famous flexibility keeping him in position to put one more ball back in play.

Down Under, though, those skills went missing. Based on 278 charted matches since the start of 2015, the following table shows the percentage of points each year that he takes to seven shots or more, and his success rate in those rallies:

Year  7+ Freq  7+ Win%  
2015    23.3%    54.9%  
2016    26.7%    53.1%  
2017    29.1%    53.3%  
2018    24.4%    52.6%  
2019    25.0%    55.1%  
2020    26.0%    54.3%  
2021    23.8%    53.6%  
2022    23.2%    54.7%  
2023    23.4%    54.1%  
2024    26.0%    49.8%

By the standards of tennis’s small margins, that’s what it looks like to fall off a cliff. The situation probably isn’t quite so bad: The sample from 2024 is limited to only the matches against Lehecka, de Minaur, Prizmic, Fritz, and Sinner. On the other hand, matches charted in previous years also skew in favor of novelty, so upsets, close matches, and elite opponents are overrepresented there too.

It is especially unusual for Djokovic to see such a decline on hard courts. Over the last decade, he has gone through spells when he loses more long rallies than he wins. But they typically come on clay. Carlos Alcaraz shut him down in last year’s Wimbledon final as well, winning 57% of points that reached the seventh shot and 63% of those with ten or more strokes. The only period when hard-court Novak consistently failed to win this category was late 2021, when Medvedev beat him for the US Open title (and then outscored him in long rallies in Paris), and Alexander Zverev won 62% of the seven-plusses (and 70% of ten-plusses!) to knock him out of the Tour Finals.

Protracted rallies are a young man’s game, and Djokovic’s results are starting to show it. Before dissecting Alcaraz in Turin last November, Novak had never won more than half of seven-plusses against Carlitos. He has barely held on against Sinner, winning 43% of those points in their Tour Finals round-robin match and 51% at the Davis Cup Finals. In 13 meetings since 2019, Medvedev has won more of these long rallies than Djokovic has. Zverev, too, has edged him out in this category since the end of 2018.

Against the rest of the pack, Djokovic manages just fine. He dominates seven-plusses against Casper Ruud and Stefanos Tsitsipas, for instance. But it’s one of the few chinks in his armor against the best, and if January represents anything more than the temporary struggles of an ailing star, more players are figuring out how to take advantage.

Avoiding danger

For players who lose a disproportionate number of long points, the best solution is to shorten them. Djokovic may never have thought in exactly those terms, but perhaps with an eye toward energy conservation, he has done exactly that.

Especially from 2017 to 2022, Novak drastically reduced the number of points that reached the seven-shot threshold:

In 2017, 29% of his points went that long; in 2022 and 2023, barely 23% did. It remains to be seen whether January 2024 is more than a blip. In his up-and-down month, Novak remained able to control his service points, but he was less successful avoiding the grind on return. As we’ve seen, that’s dangerous territory: Djokovic won a healthy majority of the short points against Fritz but was less successful in the long ones, especially following the American’s own serve.

Much rests on the direction of these trends. If the players Djokovic has faced so far this year can prevent him from finishing points early, how will he handle Medvedev or Zverev?. If Novak can’t reliably outlast the likes of Fritz and Prizmic, what are his chances against Alcaraz?

Djokovic is well-positioned to hold on to his number one ranking until the French Open, when he’ll be 37 years old. By then, presumably, he’ll be clear of the ailments that held him back in Australia. Still, holding off the combination of Sinner, Alcaraz, Medvedev, Zverev, and Father Time will be increasingly difficult. The 24-time major champion will need to redouble the tactical effort to keep points short and somehow recover the magic that once made him so implacable in the longest rallies. Age is just a number, but few metrics are so ruthless in determining an athlete’s fate.

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Arina Rodionova on the cusp of the top 100

In December, Australian veteran Arina Rodionova celebrated her 34th birthday. Now she’s competing at the tour-level event in Hua Hin this week, sporting a new career-best ranking of 101. With a first-round upset win over sixth-seed Yue Yuan, she’s up to 99th in the live rankings. Her exact position next Monday is still to be determined–a few other women could spoil the party with deep runs, or she could climb higher with more victories of her own–but a top-100 debut is likely.

Rodionova, assuming she makes it, will be the oldest woman ever* to crack the top 100 for the first time. The record is held by Tzipi Oblizer, who was two months short of her own 34th birthday when she reached the ranking milestone in 2007. Rodionova will be just the fifth player to join the top-100 club after turning 30.

* I say “ever” with some caution: I don’t have weekly rankings before the mid-80s, so I checked back to 1987. Before then, the tour skewed even younger, so I doubt there were 30-somethings breaking into the top 100. But it’s possible.

Here is the list of oldest top-100 debuts since 1987:

Player                    Milestone  Age at debut  
Arina Rodionova*         2024-02-05          34.1  
Tzipi Obziler            2007-02-19          33.8  
Adriana Villagran Reami  1988-08-01          32.0 
Emina Bektas             2023-11-06          30.6  
Nuria Parrizas Diaz      2021-08-16          30.1  
Mihaela Buzarnescu       2017-10-16          29.5  
Julie Ditty              2007-11-05          28.8  
Eva Bes Ostariz          2001-07-16          28.5  
Maryna Zanevska          2021-11-01          28.2  
Ysaline Bonaventure      2022-10-31          28.2  
Mashona Washington       2004-07-19          28.1  
Laura Pigossi            2022-08-29          28.1  
Maureen Drake            1999-02-01          27.9  
Hana Sromova             2005-11-07          27.6  
Laura Siegemund          2015-09-14          27.5

* pending!

I extended the list to 16 places in order to include Laura Siegemund. She and Buzarnescu are the only two women to crack the top 100 after their 27th birthdays yet still ascend to the top 30. The odds are against Rodionova doing the same–the average peak of the players on the list is 67, and the majority of them achieved the milestone a half-decade earlier–but you never know.

A triumph of scheduling

Rodionova has truly sweated her way to the top. She played 105 matches last year, winning 78 of them, assembling a haul of seven titles and another three finals. When I highlighted the exploits of Emma Navarro a couple of weeks ago, I couldn’t help but draw attention to the Australian, who is one of only two women to win more matches than Navarro since the beginning of last year. Iga Swiatek is the other.

Most of the veteran’s recent triumphs–44 match wins and five of her seven 2023 titles–have come at the ITF W25 level. She didn’t beat a single top-200 player in those events, and she faced only five of them. In her long slog through the tennis world last year, Rodionova played just one match against a top-100 opponent, and that was a loss to 91st-ranked Dalma Galfi.

The point is, the Aussie earned her ranking with quantity, not quality. No shame in that: The WTA made the rules, and the Australian not only chose a schedule to maximize her chances of climbing the ranking table, she executed. Kudos to her.

What her ranking does not mean, however, is that she is one of the 100 best players in the world. Elo is a more reliable judge of that, and going into this week, the algorithm ranks her 207th. (She peaked in the 140s, back in 2017.) You can hack the WTA rankings with a punishing slate of ITFs, but it’s much harder to cheat Elo.

Here are the players in the official top 150 who Elo considers to be most overrated:

Player             Elo Rank  WTA Rank  Ratio  
Caroline Dolehide       124        41    3.0  
Peyton Stearns          145        54    2.7  
Arantxa Rus             103        43    2.4  
Tatjana Maria            94        44    2.1  
Arina Rodionova         207       101    2.0  
Laura Pigossi           221       114    1.9  
Elina Avanesyan         120        62    1.9  
Varvara Gracheva         89        46    1.9  
Nadia Podoroska         127        67    1.9  
Lucia Bronzetti         109        58    1.9  
Dayana Yastremska        54        29    1.9

Once you climb into the top 100, savvy scheduling is increasingly impractical. Instead, this kind of gap comes from a deep run or two combined with many other unimpressive losses. Caroline Dolehide reached the final in Guadalajara followed by a quarter-final exit at a WTA 125, then lost three of five matches in Australia. Arantxa Rus won the title in Hamburg and reached a W100 semi-final, then lost five of six. The WTA formula lets you keep all the points from a big win for 52 weeks; Elo takes them away if you don’t keep demonstrating that you belong at the new level.

The sub-200 Elo rank suggests that Rodionova will have a hard time sustaining her place on the WTA list once the ranking points from her W25 titles start to come off the board. Until then, she can continue to pad her total and–fingers crossed–enjoy the hard-earned reward of a double-digit ranking.

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The Improbable Rise of Emma Navarro

Also today: New stat leaderboards

Emma Navarro at the 2023 US Open. Credit: Hameltion

When Emma Navarro beat Elise Mertens for her first WTA title in Hobart on Saturday, it was only part of a natural progression. For more than a year now, she has shown a knack for winning, regardless of level, surface, or just about anything else. While most fans still don’t know her name, she’s up to 26th in the official rankings and 22nd on the Elo list.

The former collegiate champion–winner of the national title as a Virginia Cavalier in 2021–started her 2023 campaign just inside the top 150. She arrived at the brink of the top 100 with back-to-back ITF titles on clay in April, then cracked the top 60 with a grass-court final in Ilkley. Her first top-ten win came in September on hard courts, against Maria Sakkari in San Diego, and after a busy fall that included another two ITF titles, she broke into the top 40. She’s 8-1 so far in 2024; the only blip is a loss to Coco Gauff.

Altogether, that’s 72 victories since the beginning of last year. Not many women can boast so much success at the W25 level or higher in that span:

Player                   2023-24 Wins  
Arina Rodionova                    79  
Iga Swiatek                        73  
Emma Navarro                       72  
Oceane Dodin                       64  
Jessica Pegula                     62  
Julia Riera                        59  
Aryna Sabalenka                    59  
Martina Capurro Taborda            59  
Yafan Wang                         58  
Carlota Martinez Cirez             57

The remarkable part of Navarro’s rise is not the sheer quantity of positive results; it’s that she rose through the rankings so fast at the age she did. She first cracked the top 100 last May just before her 22nd birthday–hardly old by any rational standards, but nearly geriatric on the youth-driven WTA tour. The 25 players standing in front of Navarro in this week’s rankings broke into the top 100, on average, before their 20th birthday: The median is Aryna Sabalenka’s arrival at 19 years, 5 months. Late developers like Jessica Pegula, Barbora Krejcikova, and Navarro are exceptions to a long-standing rule.

It’s not unusual for a player to finally achieve a double-digit ranking when they are 21 or older, but it’s rare for a future star to do so–and now that Navarro is a tour-level title-holder ensconced in the top 30, she deserves that label. Since 1990, there have been 207 players who finished their age-21 season ranked between 101 and 200 without a previous appearance in the top 100. Only 25 of them reached #100 at the end of the following year; Navarro was only the fourth to crack the top 50.

Of those 200-plus players, only 35 of them ever achieved a top-40 ranking. (A few more, including Katie Boulter and Katie Volynets, could still join the group.) On average, it took them 1437 days–just short of four years–to do so. Navarro needed only 315 days, the second-fastest in the last 30-plus years. Here are the players who made the fastest move from the end of their age-21 season to the top 40:

Player                 Age 21  top 40 debut  Days  
Elise Mertens            2016    2017-08-28   245  
Emma Navarro             2022    2023-11-06   315  
Veronika Kudermetova     2018    2019-11-11   315  
Kurumi Nara              2012    2014-06-09   525  
Jamie Hampton            2011    2013-06-24   546  
Casey Dellacqua          2006    2008-07-28   581  
Tathiana Garbin          1998    2000-09-25   637  
Liudmila Samsonova       2019    2021-11-01   672  
Bethanie Mattek Sands    2006    2008-11-03   679  
Anne Kremer              1996    1999-04-12   833  
Jil Teichmann            2018    2021-04-26   847  
Zi Yan                   2005    2008-05-05   861  
Paula Badosa             2018    2021-05-24   875  
Yone Kamio               1992    1995-06-12   896  
Alison Riske Amritraj    2011    2014-06-09   896  
Johanna Konta            2012    2016-02-01  1127

It’s possible that Navarro could have been ready for the big time earlier had she not spent two years playing college tennis. Her sub-100 ranking at the end of 2022 was partly due to a limited schedule, as she played only a handful of tournaments before leaving school after the spring semester that year. But she wasn’t playing top-100 tennis when she did step on court: Elo ratings respond much more quickly to quality results (and do not reward quantity for its own sake), and her ranking by that algorithm, 148th, was virtually identical to her place on the official list.

Whatever the benefits and (temporary) costs of her stay at the University of Virginia, Navarro seemed to learn from the step up in competition–and quickly. She lost her first 11 matches against the top 50; in the last four months, she has won 5 of 6.

What works

The most memorable victory so far was Saturday’s triumph over Mertens for a debut WTA title. It was a grind, taking two hours, 50 minutes, and spanning 14 breaks of serve en route to a 6-1, 4-6, 7-5 finish. There was little first-strike tennis on display, as the average point ran to 5.5 strokes. 69 points required seven shots or more, and 37 reached double digits.

The battle for openings worked to Navarro’s advantage. In a sample of eleven previous matches logged by the Match Charting Project, she struggled in longer rallies, winning just 46% of points that reached a seventh shot compared to 49% overall. On Saturday, she reversed that trend in a big way, out-point-constructing her veteran opponent and winning a whopping 59% of the longer points. Of 84 charted Mertens matches, it was only the eighth time that she played at least 20 long points and won so few of them. Among the few players to beat her so soundly on rally tactics: Pegula and Simona Halep.

While Navarro’s results have steadily improved, her game plan is still recognizable form her days as a college champion. After defeating Miami’s Estrela Perez-Somarriba for the 2021 NCAA title, she described her approach: “I was able to dictate with my forehand and finish a lot of points with my backhand.” In Hobart, her backhand continued to populate the highlight reel, with seven clean down-the-line winners. But it was the forehand that opened the court in the first place.

She played, essentially, a clay-court match, using the forehand to create opportunities for the next ball. She hit winners with 7% of her forehand groundstrokes, slightly below tour average. But when she was able to hit a forehand, she won the point 62% of the time, an outstanding figure for a close match. One point serves as an illustration of the rest: At 2-all, 15-all in the third set, Navarro converted a return point with a down-the-line backhand winner on the 14th shot of the rally. After a deep forehand return, Navarro was forced to hit two backhands. When she was finally able to deploy the forehand on the 8th shot, she stabilized the point by going down the middle. The 10th shot took advantage of a let cord with a heavy crosscourt forehand, a weapon that worked in her favor on Saturday more than two-thirds of the time. Her next forehand went the other direction, creating the space for–finally–a backhand out of the Belgian’s reach.

While not every point was quite so tactical, point construction always lurked. Mertens frequently attempted a pattern where she would go the same direction with two consecutive groundstrokes then, having wrong-footed Navarro with the second of them, go for a winner. The sequence doesn’t work against a big swinger because the points don’t last long enough. That wasn’t a problem against the American, but Navarro’s resourcefulness nullified the tactic nonetheless. Unlike many players her age, Navarro is able to use slices off both wings to neutralize points, and she often did so on the second shot of Mertens’s would-be pattern. The Hobart champion hit 40 slices over the course of the match, ultimately winning the point on 20 of them. For a defensive shot, rescuing 50% of those situations counts as a victory.

There is little in Navarro’s game that advertises her as a world-beater: The weapons I’ve described work best as part of a carefully-managed package. She may prove to be most dangerous on clay, where aggressive opponents will have a harder time keeping points short. She might also develop yet another level. Twelve months ago, only a reckless forecaster would have predicted she could rise so high, so quickly. We still haven’t seen her peak.

* * *

Deep leaderboards

Among the cult favorites on the Tennis Abstract site are the tour leaderboard pages, which contain nearly 60 sortable stats for the top 50 players on each circuit. Many of those stats aren’t available anywhere else, including things like average opponent ranking and time per match. It’s also possible to filter the matches for each calculation to determine things like the best hold percentages on clay.

Last week I introduced three new pages that extend the same concept:

Here’s just one example of what’s possible, the best WTA players outside the top 50 by ace percentage:

These are a great way to identify standout skills of lesser-known players. All of the leaderboards update every Monday.

* * *

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August 23, 1973: One Perfect Truth

Stan Smith, Ilie Năstase, and Tom Okker

Major tournament committees never had an easy job. Given a pile of national and regional rankings–sometimes many months out of date–and another pile of entry forms, they had to decide who could play their event. Then, with the field in place, they had to decide on the seedings.

It was an art, not a science. Rankings were published just once a year. Beyond the first ten, few lists compared players across national borders. In both ranking lists and entry decisions, there were biases, both acknowledged and obscured. Players complained of a “star system,” in which famous names were given priority over superior players. Insiders, especially members at clubs where tournaments were held, had an edge. Young players benefited from well-connected coaches.

So it had been for half a century. Tournament entries hadn’t always been an issue: There was usually enough room in the bracket for everyone. In the early days, draws were arranged at random. It took a run of disastrous bad luck for officials to decide to keep top players away from each other. At the US National Championships in 1921, the paths of the two best men players–Big Bill Tilden and Little Bill Johnston–intersected in the fourth round. The women’s draw was even worse: Visiting sensation Suzanne Lenglen drew home favorite Molla Mallory in the second round. It is no exaggeration to say that the latter quirk of fate–and Suzanne’s loss by retirement–altered the course of tennis history.

Within six months, USLTA tournament draws were seeded.

In 1973, the system underwent a change almost as significant as the adoption of seeding. On August 23rd, the new men’s players’ union, the ATP, released its first set of rankings.

There was no bias in the ATP’s calculation, aside from the tendencies of an imperfect algorithm. Players were given points for their performance at each tournament, then assigned an overall total based on their average over the past year.

The ATP’s list didn’t immediately rise to the top of the heap. The same week, the US Open announced its seeding lists, based on

the U.S. Lawn Tennis Association rankings, Commercial Union Grand Prix points, World Championship Tennis records, and–for the first time–a statistical approach consisting of a new computerized ranking system developed by the Association of Tennis Professionals.

Information overload, perhaps. Committee members couldn’t decide between Ilie Năstase and Stan Smith, so they awarded the two men co-No. 1 seeds. (The ATP ranked them first and third, respectively.) The committee also acknowledged surface preferences, something that the single-number ATP formula ignored. Dirtballer Manuel Orantes ranked second on the new computer, but he was seeded eighth on the grass at Forest Hills.

Quibbles about the ranking formula are as old as the system itself. The approach of averaging tournament results, in particular, incentivized players to stick to their best surface and skip smaller events; it was possible for someone to sit out a week and see his ranking go up!

The important thing, though, was that the imperfections were the same for everyone. An algorithm could be tweaked; a small group of entrenched bureaucrats could not. Bill Scanlon, then a 16-year-old beginning to gain attention as a promising junior in Texas, later called the ATP rankings “the one perfect truth.” They weren’t perfect, but that wasn’t the point. The formula provided objective targets free of favoritism.

The biggest winners were the deserving players on the fringes. Nastase and Smith would’ve been seeded anywhere regardless of the system. Most people could agree on the top ten, give or take a name or two. But what about an American teen who grew up playing in public parks, as Bobby Riggs had done in the 1930s? Or the rising number of challengers from Eastern Bloc nations without a long history on the international scene? Outsiders could now be judged more on their performance, less on their reputation and connections.

The players, in short, had gained even more control over the game. Within a few years, most tournament committees had given up on the job of determining entries and seeds themselves. Most fans probably didn’t notice the difference. But the rise of computer rankings set the stage for a more meritocratic, more inclusive sport.

* * *

This post is part of my series about the 1973 season, Battles, Boycotts, and Breakouts. Keep up with the project by checking the TennisAbstract.com front page, which shows an up-to-date Table of Contents after I post each installment.

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Aslan Karatsev Isn’t Better Than Novak Djokovic, But…

What’s better, winning 15 of 17 matches, or going undefeated for 9?

Even if you know that the 15-2 guy is Aslan Karatsev in 2021, and the 9-0 guy is Novak Djokovic this year, there’s no obvious answer. Sure, Djokovic beat Karatsev easily, and Novak’s nine wins included a grand slam title. We know Djokovic is the better player–he’s got more than a decade of proof to support that claim–and no one in their right mind would take Karatsev’s last three months over Novak’s.

True as all of that is, it’s not the question I’m asking.

The player with the 15-2 record has two advantages over his 9-0 peer. First, he has more wins. (Mind-blowing stuff, I know.) Second and more importantly, he has more evidence of his current level, even if it includes two losses. The 9-0 guy could go undefeated for 17 matches… but he could also end up 11-6. His nine-match record simply doesn’t give us as much information.

Again, if you know which players I’m talking about, that doesn’t matter–we have 1,100 matches worth of information about Djokovic, most of which say that his 9-0 is business as usual. He might not win his next eight matches, but he’s certainly not going to lose more than a few of them.

The yElo light at the end of the tunnel

If you’ve been reading my last couple of posts, you know where I’m going with this.

Last week, I introduced the concept of yElo. The “y” stands for year, but it can be used for any unit of time shorter than an entire career. Instead of using every bit of available information, we look only at a designated time frame, such as the 2021 season. While maintaining our knowledge of other players (e.g. Andrey Rublev is a really tough opponent; Egor Gerasimov not so much), we treat each player as if we know nothing else about him.

So truly, we’re comparing Karatsev’s 15-2 with Djokovic’s 9-0, taking into account the quality of their competition.

Plug every ATPer’s 2021 season into the formula, and here are the yElo leaders, through last weekend’s finals in Dubai and Acapulco:

Rank  Player                  W-L  yElo  
1     Aslan Karatsev         15-2  2082  
2     Novak Djokovic          9-0  2081  
3     Daniil Medvedev        13-2  2061  
4     Andrey Rublev          15-3  2006  
5     Marton Fucsovics       14-4  2000  
6     Stefanos Tsitsipas     14-4  1983  
7     Alexander Zverev        9-4  1922  
8     Matteo Berrettini       8-2  1918  
9     Jeremy Chardy          13-6  1915  
10    Lloyd Harris           11-5  1878  
11    Jannik Sinner           9-4  1848  
12    Alexei Popyrin          9-3  1836  
13    Roberto Bautista Agut   8-7  1831  
14    Taylor Fritz            7-4  1830  
15    Sebastian Baez         14-1  1820  
16    Felix Auger Aliassime   8-4  1818  
17    Karen Khachanov         9-5  1810  
18    Mackenzie McDonald     11-5  1809  
19    Tomas Machac           10-3  1806  
20    Daniel Evans            6-3  1800

Yes, Karatsev really does outscore Djokovic. Barely.

We are accustomed to 52-week rankings and Elo ratings that carefully weigh an entire career’s worth of work. So this is a deeply weird list, with only a handful of players anywhere near where we’d expect. #15 and #19 are Challenger-level guys, for crying out loud!

Embrace the race

The official Race to Turin doesn’t look as bizarre as the yElo list, but imagine showing it to someone in December, with Karatsev 5th, Marton Fucsovics 7th, and Rafael Nadal outside the top 20. Both the Race and the yElo list are “wrong” in the traditional sense, but they tell us much more about the 2021 season than the old-fashioned rankings do.

Tennis’s relentless focus on the long view sucks some excitement out of the season. Think of virtually any team sport. A month into the season, some unheralded club has gotten off to a hot start, and at least in some quarters, that’s the story–can they keep it up? should we have seen this coming all along? Nobodies are cast in the role of front-runners, and established stars play the part of underdogs.

In tennis, nobodies are… well, nobodies who won a few matches lately. Superstars play the part of superstars who’ve been taking some time off. Sure, we know that Djokovic and Nadal are going to end up near the top of the rankings list in November, just like we know the Dodgers and Yankees will be in the playoffs. But that doesn’t mean we ought to take it as a foregone conclusion from day one. In baseball, as the saying goes, everybody’s in first place on Opening Day.

Embracing the race–focusing on which players are leading the pack at each point throughout the season–doesn’t have to mean throwing away longer-term rankings. The traditional calculations should still be used for tournament entries and (maybe) for seedings. Top players have earned as much, and tournament entry is a factor that isn’t present in the major team sports.

Everybody wants to know how the ATP will survive when the Big Three are out of the picture. Well, this is a start–pay attention to who’s winning in 2021. If we take yElo’s word for it, a virtual nobody emerged to overtake Djokovic for the #1 spot going into Miami! An Argentinian prospect is playing like a top-15 guy just by winning a bunch of Challengers! Jeremy Chardy is more than just a hitting partner for the other Frenchmen!

The stories are out there, just like they are every year. It’s a shame that they get buried by all the talk about players who won last year.

I’ve added men’s and women’s yElo ratings to the Tennis Abstract website, and they’ll be updated weekly.

The Best 22-Match yElo Streaks

Earlier this week I wrote about Garbine Muguruza’s outstanding start to the season, and I introduced a new method to quantify a player’s level in a relatively short time span. Instead of using traditional Elo, which takes into account everything we know about a player, my new metric, yElo, uses what we know about everyone else, but treats a player’s short-term performance as if it is all we know about her. The parameters for yElo, such as k-value, are the same as the ones I’ve arrived at to make “regular Elo” as predictive as possible.

In other words, we measure Muguruza’s 22 matches in 2021 as if she had never played a WTA event before. As we saw in my earlier post, this approach considers the strength of opponents each player faced, and it rates her 18-4 record as better than anyone else in 2021, including Naomi Osaka’s 10-0 start.*

* excluding walkovers, which I ignore for all versions of Elo and yElo.

Muguruza’s season start has been outstanding and it is definitely underrated by the official WTA rankings and maybe even by the race, but I don’t want to make too much of it–one title in five tournaments in hardly world-historical stuff. On the other hand, it’s a good way to get our feet wet with a new metric that I think will prove useful for a wide range of tennis comparisons.

Garbine vs Garbine

The Spaniard won majors in 2016 and 2017, and she briefly reached number one in the rankings in September of 2017. Those achievements belong on a Hall of Fame plaque over her recent Dubai title and Yarra River Classic final. But was she really playing better back then?

She was not! I ran the yElo formula for every 22-match sequence in Muguruza’s career. The best of the bunch–again, taken entirely out of context, as if we know nothing beyond those 22 matches–was a run late in 2015 when she reached the Wuhan final, won Beijing, then went undefeated in the WTA Finals round robin stage. Her yElo based on those 22 matches was 2172, narrowly better than her 2021 yElo of 2160.

The more memorable moments of her career don’t quite stack up:

Elo   W-L   Span                            
2172  17-5  2015 Wim R16 - WTA Finals RR    
2160  18-4  2021 Abu Dhabi R64 - Dubai F    
2148  18-4  2017 Birmingham R32 - Cinci F   
2122  19-3  2017 Wimb R128 - USO R16 (#1)   
2084  17-5  2017 Miami R64 - Wimb F         
2076  16-6  2016 Doha QF - Roland Garros F 

I haven’t shown every 22-match sequence of her career, because that list is long and boring–the streaks heavily overlap with each other, and thus there are often tiny differences between them. But it is instructive to look at the time periods that ended at key moments.

The best of that bunch was the 22-match run ending with Muguruza’s 6-1 6-0 beatdown of Simona Halep at the 2017 Cincinnati final. That set the stage for her ascent to #1, though the ranking move didn’t happen until after the US Open. That streak is close to her current level. The 22 matches leading up to the official #1 takeover are a bit lower (she lost to Petra Kvitova at the US Open, which was less forgivable then than now), and the timespans ending with her two slam finals are still further down the list.

Don’t misunderstand–Muguruza was playing very well throughout all of these time periods. But when we crunch the numbers, we find that her current level is roughly on par with the best she’s ever played.

Garbine vs the world

Metrics are a lot more informative once we gain some context. Many of you probably have a good sense of what regular Elo ratings mean–2100+ is outstanding, 2000+ is top ten-ish, 1900+ is approximately the top 20, and so on. We can piggyback on that for yElo. When Muguruza’s 22-match yElo this season is 2160, it really does mean that, when feeding that very limited set of results into the Elo formula, it thinks Muguruza’s level is close to that of the best player in the world.

Well… the best player in the world right now. There’s no truly dominant force in women’s tennis at the moment, so we’re not seeing players at the top end of the all-time Elo scale. In regular Elo, peak Martina Navratilova and peak Steffi Graf topped 2600, more than 400 points above Osaka’s current rating of 2189. It will not surprise you, then, to learn that Navratilova, Graf, Serena Williams, Chris Evert, and many others put together 22-match runs* that make Muguruza’s 2021 season look positively pedestrian.

* yes, I know how ridiculous it is that this whole article is based on the arbitrary 22-match time span. We could do the same stuff with the more natural-sounding 20-match span, but there wouldn’t be an intuitive way to fit Muguruza’s current run into the discussion. And let’s face it, 20 is just as arbitrary as 22.

Out of my entire database on women’s tennis results going back to 1950 or so, about 100 women have enjoyed a 22-match run that outscores Muguruza’s best. The top of the list is the end of Navratilova’s 1983 season, which is worth a yElo of 2445. Close behind is Monica Seles, who reached 2438 with a streak starting at the end of 1992 and extending into the 1993 season. Three more women topped 2400, another 27 exceeded 2300, and 46 more put together 22 consecutive matches worth at least 2200.

Here are the 15 active women who’ve played at least as well as Muguruza for their best 22-match spans:

yElo  Player                W-L   Year(s)  
2389  Serena Williams       21-1  2001-02  
2386  Venus Williams        22-0  2000     
2335  Kim Clijsters         20-2  2002-03  
2332  Victoria Azarenka     22-0  2012     
2234  Vera Zvonareva        18-4  2008     
2217  Svetlana Kuznetsova   19-3  2004     
2217  Naomi Osaka           20-2  2019-20  
2209  Samantha Stosur       20-2  2010     
2205  Petra Kvitova         19-3  2011-12  
2205  Simona Halep          20-2  2018     
2196  Caroline Garcia       18-4  2017     
2186  Ashleigh Barty        19-3  2019     
2180  Angelique Kerber      18-4  2015-16  
2174  Carla Suarez Navarro  18-4  2015     
2172  Garbine Muguruza      17-5  2015

With the caveat that I haven’t spent much of my life thinking about the best 22-match runs in women’s tennis history, this seems like a credible list. I particularly like how yElo manages to consider strength of opponent to the point that an 18-4 run*, like Zvonareva’s in 2008, can outrank so many 20-2s. (Vera even beats a few 22-0s from the amateur era.)

* the link shows a few extra matches–the 18-4 run starts in the QFs of Guangzhou and ends in the Tour Finals semi-final. Note again that yElo skips retirements.

I hope you find the new yElo metric as interesting as I do. I’ll definitely be doing more with it, since I suspect it has value even outside the narrow context of one player and a single timespan of arbitrary lenth.

Repurposing Elo for Streaks, Seasons, and Garbine Muguruza

Elo is a fantastic tool for its explicit purpose: estimating the skill level of players based on available information. For instance, my WTA ratings currently rank Ashleigh Barty second. That seems plausible enough–it may be correct to give her the edge in a head-to-head matchup with everyone on tour except for Naomi Osaka. But with women pursuing such different schedules this season, a rating is only so useful.

For all of Barty’s or Osaka’s skill, is it right to say either one of them has had a better 2021 season than Garbine Muguruza? Osaka won the Australian Open, so she has a valid claim. Barty’s argument is a lot more tenuous, based on only eight victories. The Spaniard’s case writes itself–only a handful of players are up to double digits in wins this year, and Muguruza already has 18. How could we decide? If Elo is the smart version of the official rankings, what’s the smart version of the official race?

Starting fresh

The Elo algorithm itself offers a solution. A big part of the reason Muguruza is rated 4th on my current Elo list–and not higher–is her career before 2021. We had hundreds of matches worth of data on Garbine before January 1st, and it would be silly to throw all that away. Her 18-4 start is fantastic, but it doesn’t supersede everything that came before. It just gives us reason to update our rating.

Here’s where the ranking/race analogy is useful. The official rankings use a time span of 52 weeks (or more). The race restarts on January 1st. We could do the exact same thing with Elo, throwing away all results from the previous year and starting over, but that would be wasteful–it wouldn’t allow us to take into account whether players had faced particularly easy or tough draws, for instance.

The solution is to set Elo ratings back to zero (or 1500, in Elo parlance) one player at a time.

Take Muguruza. Instead of starting the year with a rating of 1981 and a history of several hundred matches, we pretend to know nothing about her. We give her a newbie’s rating of 1500 and a history of zero matches. Then we run the Elo algorithm to update her rating over the course of her 22 matches. First she faces Kristina Mladenovic (with her actual rating at the time of 1817), and improves to 1605. Then she beats Aliaksandra Sasnovich (and her rating of 1805), and improves to 1692. Repeat for each of her 2021 results, and the end result is a rating of 2160–almost 100 points higher than her current “real Elo” rating and within shouting distance of Osaka’s 2189.

To compare players, work through the same steps for everybody else, calculating their current-season rating as if they played their first career match in January.

It’s worth taking a moment to think about exactly what we’re measuring. That outstanding 2160 rating is what you get if a complete unknown shows up with zero match experience, then goes on the 22-match run that has been Muguruza’s season so far. The difference between real-Garbine and fake-newbie-Garbine is that the real one has an extensive track record that tells us she’s always been good–but that she probably isn’t quite this good.

I call it … yElo

This approach is “Elo for seasons” or “year Elo”–yElo*. It doesn’t have to be limited to calendar years, as the same approach would be useful to comparing, say, 20-match segments. It allows us to take advantage of the Elo algorithm–and the well-informed ratings of other players–to measure partial careers.

* you can pronounce it like the color “yellow,” but I prefer to say it like Phil Dunphy from Modern Family answering the phone.

Muguruza’s 2160 rating sure looks good, so how does it stack up against the rest of the tour? Here’s the 2021 top 20, considering players with at least five match wins through the Dubai and Guadalajara finals last weekend:

Rank  Player                W-L  yElo  
1     Garbine Muguruza     18-4  2160  
2     Naomi Osaka          10-0  2094  
3     Jessica Pegula       15-5  2002  
4     Serena Williams       8-1  1997  
5     Elise Mertens        11-2  1971  
6     Karolina Muchova      7-1  1953  
7     Aryna Sabalenka      11-4  1943  
8     Iga Swiatek          10-3  1941  
9     Daria Kasatkina      10-4  1910  
10    Barbora Krejcikova   10-5  1905  
11    Shelby Rogers         9-4  1902  
12    Jil Teichmann         9-5  1899  
13    Anett Kontaveit       9-4  1897  
14    Jennifer Brady        9-4  1892  
15    Cori Gauff           11-5  1885  
16    Danielle Collins      9-4  1883  
17    Ashleigh Barty        8-2  1878  
18    Sara Sorribes Tormo   9-2  1867  
19    Ann Li                5-1  1864  
20    Simona Halep          6-2  1854 

Like any Race list in March, this isn’t really reflective of skill. But when we consider the small amount of data it has to work with for each player, it’s … pretty good?

Again, you can quibble over whether Osaka or Muguruza has had the better season, but this approach weighs the better winning percentage and stronger average opponent against the much higher absolute win count and gives us a credible answer. Muguruza’s additional evidence of good tennis playing puts her ahead of Osaka’s evidence of short-term unbeatability.

While yElo is basically just a toy–it certainly doesn’t have the same predictive value as regular Elo–this initial look makes me like it. The possibilities are endless, from more sophisticated race tracking, to ranking the greatest seasons of all time, to comparing a player’s current hot streak to what’s she’s done in the past. Stay tuned, as I’m sure I’ll have more yElo results to report in the future.