Rethinking the Mental Game

Italian translation at settesei.it

Everyone seems to agree that a huge part of tennis is mental. It’s less clear exactly what that means. Pundits and fans often say that certain players are mentally strong or mentally weak, attributes that help explain the gap when there’s a mismatch between talent and results.

Here are three more adjectives you’ll hear in ‘mental game’ discussions: clutch, streaky, consistent. I’ve frequently railed against commentators’ overuse of these terms. For instance, hitting an ace facing break point is ‘clutch,’ in the sense that the player executed well in a key moment. But that doesn’t mean the player himself can be described as clutch. Just because he sometimes performs well under pressure doesn’t mean he does so any more than the average player. Same goes for ‘streaky’–humans tend to overgeneralize from small samples, so if you see a player hit three down-the-line backhand winners in a row, you’ll probably think it’s a hot streak, even though such a sequence will occasionally arise by luck alone.

Some players probably are more or less clutch, more or less streaky, or more or less consistent than their peers, even beyond what can be explained by chance. At the same time, no tour pro is so much more or less clutch that their high-leverage performance explains a substantial part of their success or failure on tour. Most players win about as many tiebreaks as you’d expect based on their non-tiebreak records and convert about as many break points as you’d predict based on their overall return stats. Nothing magical happens in these most-commonly cited pressure situations, and no player becomes either superhuman or completely hopeless.

If you’re reading my blog, you’ve probably heard most of this before, either from me or from innumerable other sports analysts. I’m not taking the extreme position that there is no clutch (or streakiness or consistency), but I am pointing out that these effects are small–so small that we are unlikely to notice them just by watching matches, and sometimes so tiny that even analysts find it difficult to differentiate them from pure randomness.

Still, we’re left with the unanimous–and appealing!–belief that tennis is a mental game. In trying to explain various simplified models, I’ll often say something like, “this is what it would look like if players were robots.” Even though some of those models are rather accurate, I think we can all agree that players aren’t robots, Milos Raonic notwithstanding.

Completely mental

An extreme version of the ‘mental game’ position is one I’ve heard attributed to James Blake, that the difference between #1 and #100 is all mental. (I’m guessing that’s an oversimplification of what Blake thinks, but I’ve heard similar opinions often enough that the general idea is worth considering.) That’s a bit hard to stomach–does anybody think that Radu Albot (the current No. 99) is as talented as Rafael Nadal? But once we backtrack a little bit from the most extreme position, we can see its appeal. At the moment, both Bernard Tomic and Ernests Gulbis are ranked between 80 and 100. Can you say with confidence that those guys aren’t as talented as top-tenners Kevin Anderson or Marin Cilic? Yet Tomic often excels in pressure situations, and Cilic is the one known to crumble.

The problem with Tomic, Gulbis, and so many of the innumerable underachievers in the history of sport, isn’t that they fall apart when the stakes are high. We can all remember matches–or sets, or other long stretches of play–in which a player seems uninterested, unmotivated, or just low-energy for no apparent reason. Even accounting for selection bias, I think the underachievers are more likely to provide these inexplicably mediocre performances. (Can you imagine Nadal appearing unmotivated? Or Maria Sharapova?) In a very broad sense, I could be talking about streakiness or consistency here, but I don’t think it’s what people usually mean by those two terms. It operates at a larger scale–an entire set of mediocrity instead of say, three double faults in a single game–and it offers us a new way of thinking about the mental aspect of tennis.

Focus

Let’s call this new variable focus. There are millions of potential distractions, internal and external, that stand in the way of peak performance. The more a player is able to ignore, disregard, or somehow overcome those distractions, the more focused she is.

Imagine that every player has her own maximum sustainable ability level, and on a scale of 1 to 10, that’s a 10. (I’m saying ‘sustainable’ to make it clear that we’re not talking about ninja Radwanska behind-the-back drop-volley stuff, but the best level that a player can keep up. Nadal’s 10 is different from Albot’s 10.) A rating of 1, at the bottom of the scale, is something we rarely see from the pros–imagine Guillermo Coria or Elena Dementieva getting serve yips. The more focused the player, the more often she’s performing at a 10 and, while she may not be able to sustain that, the more focused player remains closer to a 10 more of the time.

This idea of ‘focus’ sounds a lot like the old notion of ‘consistency’, and maybe it’s what people really mean when they call a player consistent. But there are several reasons why I think it’s important to move away from ‘consistency.’ The first one is pedantic: ‘consistent’ isn’t necessarily good. If you tell a player to be consistent and she hits nothing but unforced errors on her forehand, she has followed your directions by being consistently bad. More seriously, ‘consistency’ is often conflated with ‘low-risk’, which is a strategy, not a positive or negative trait. A player like Petra Kvitova will never be consistent–her signature level of aggression will always result in plenty of errors, sometimes ugly ones, and occasionally in ill-timed bunches. Even an optimized strategy for a highly-focused Kvitova will appear to be inconsistent.

If you’re the type of person who thinks a lot about tennis, you probably see the limitations in my definition of consistency. I agree: The concept I’ve knocked down is a bit of a strawman. If I could do a better job of consisely defining what tennis people talk about when they talk about consistency, I would–again, part of the problem is that the term is overloaded. Even if you mean ‘focus’ when you’re saying ‘consistency,’ I think it’s valuable to use a separate term with less baggage.

Chess

Is ‘focus’ any better than the other mental-game concepts I’ve knocked down? We can objectively measure clutch effects, but it’s a lot harder to look at the data from a match or an entire season and quantify a player’s level of focus.

Nonetheless, I strongly suspect that at the elite level, focus varies more than, say, micro-level streakiness. Put another way: The difference in focus among top players has the potential to explain much of their difference in performance.

I started to think about the importance of focus–again, the ability to sustain a peak or near-peak level for long periods of time–while following last month’s World Chess Championship between Magnus Carlsen and Fabiano Caruana. (I wrote about the chess match here.) Chess is very different from tennis, of course. But because it doesn’t rely on physical strength, speed, or agility at all, it has a much stronger claim to the ‘mental game’ moniker than tennis does. While flashes of brilliance have their place in chess, classical games require sustained concentration at a level that few of us can even fathom. One blunder against an elite player, and you might as well give up and get some extra rest before the next game.

A common stereotype of a chess grandmaster is an old man, whose decades of knowledge and savvy help him brush aside younger upstarts. Yet Carlsen and Caruana, the two best chess players in the world, are in their mid-20s. The current top 30 includes only four men born before 1980. 12 of the top 30 were born in the 1990s, two of them since 1998. The age distribution in elite chess is awfully similar to that of elite tennis.

The aging curve in tennis lends itself to easy explanations: Players can start reaching the top when they hit physical maturity in their late teens, they continue to improve throughout their 20s as they gain experience and enjoy the benefits of physical youth, and then physical deterioration creeps in, beginning to have an effect in the late 20s or early 30s and increasing in severity over time. There’s obviously some truth in that. No matter how important the mental aspect of tennis, it’s hard to compete once you’ve lost a step, and even harder with chronic back or knee pain.

Yet the chess analogy persists: If tennis were mental, with much of the variation between elites explained by focus, the aging curve would look about the same. As modern science has improved training, nutrition, and injury recovery–thus reducing the effect of physical deterioration–tennis’s aging curve has developed a flatter plateau in the late 20s and 30s. In other words, as physical risks are mitigated, the elite career trajectory of tennis looks even more like that of chess.

Thinking ahead

For now, this is just a theory. Maybe you agree with me that it’s a very appealing one, but it remains untested, and it’s possibly very difficult to test at all.

If sustained focus is such a key factor in elite tennis performance, how would we even identify it? The most direct way would be to avoid the tennis court altogether and devise experiments so that we could measure the concentration of top players. I doubt we could convince the ATP top 100 to join us in the lab for a fun day of testing. There is some long-term potential, though, as national federations could do just that with their rising stars. Some might be doing so already; some professional baseball and American football teams administer cognitive tests to potential signees as well.

Unfortunately, we can’t make the best tennis players in the world our guinea pigs. If we looked instead at match-level results, we could try to measure focus using a similar approach to what I’ve done before in the name of quantifying consistency (oops!). My earlier algorithm attempted to measure the predictability of a player’s results–that is, is the 11th best player usually losing to the top ten and beating everyone else, or are his results less predictable? That’s not what we’re interested in here, because by that definition, ‘consistency’ isn’t necessarily good.

We could work along similar lines, though. Given a year or more or results, we could estimate a player’s peak level, perhaps by taking the average of his five best results. (His absolute best result might be the result of an injured opponent, an untimely rain delay, or something else unusual.) That would indicate the level that marks a ’10’ on his personal scale of 1 to 10. Then, compare his other results to that peak. If most of his results are close to that level–like the ‘consistent’ player who loses to the top ten and beats everyone else–he appears to be focused, at least from one match to the next. If he has a lot of bad losses by comparison, he is failing to sustain a level we know he’s capable of.

That sort of approach isn’t entirely satisfying, as is often the case when working with match-level stats. Perhaps with shot-level or camera-based data, we could do even better. Using a similar approach to the above–define a peak, compare other performances to that peak–we could look at serve speed or effectiveness, putting returns in play, converting opportunities at net, and so on. It would be complicated, in part because opponent quality and surface speed always have the potential to impact those numbers, but I think it’s worth pursuing.

If I’m right about this–that tennis isn’t just a mental game, it’s a game heavily influenced by sustained concentration–the long term impact is on player development. Academies and coaches already spend plenty of time off court, talking tactics and utilizing insights from psychology. This would be a further step in that direction.

The mental side of tennis–and sports in general–remains a huge mess of unknowns. As the next generation of elite players tries to develop small technical and tactical improvements in order to find an edge, perhaps the mental side is the next frontier, one that would finally enable a new generation to sweep away the old.

Maybe, Finally, The Next Generation is Here

Italian translation at settesei.it

Alexander Zverev is winning Masters titles. Stefanos Tsitsipas is beating top ten players. Denis Shapovalov, Frances Tiafoe, and even Alex De Minaur are making life more difficult for ATP veterans.

For most of the last decade, the story of men’s tennis has been the degree to which the game is getting older. Even now, thirty-somethings hold half of the places in the top ten. Wave after wave of hyped prospects have failed to take over the sport, settling in for a long fight to the top.  On Monday, Juan Martin del Potro, once hailed as the man who would topple the Big Four, will reach a new career-best ranking of No. 3 … six weeks away from his 30th birthday.

At last, though, men’s tennis appears to be getting younger. Teenagers Shapovalov, Tiafoe, and De Minaur are rising just as some of the game’s crustiest vets are on their way out: 36-year-olds David Ferrer and Julien Benneteau are calling it quits this year, tumbling in the rankings alongside the likes of Feliciano Lopez and Ivo Karlovic.

The result is that the average age of the ATP top 50 is falling–something it hasn’t done for a really, really long time. The following graph shows the average age of the top 50 at the end of every season since 1983, plus–the rightmost data point–the mean age of the current top 50:

At the end of 2017, the average age was 29.0 years; it has since fallen to 27.75. That’s bigger than any single-year swing (up or down) in the last 35 years. As the graph shows, there were plenty of “down” years in the late 1990s and early 2000s, but none of them had even half the magnitude of the current drop.

There’s still an enormous gap between the current state of affairs and the days when men’s tennis was young. If we expand our view to the top 100, this year’s shift is less dramatic–with Ferrer, Benneteau, Lopez and others ranked between 51 and 100, that average still sits at 28.1 years, only about seven months younger than the corresponding number at the end of last season. But even that weaker evidence of a youth movement points in the same direction: 28.1 years is the youngest the top 100 has been since 2012.

Barring fundamental changes in rules or equipment, we’re unlikely to return to the teenage-driven game of the early 1990s. But after a decade of waiting, watching, and wondering, we can see some cracks in the greatest generation of men’s tennis. And finally, there’s a group of young players ready to take advantage.

The Unique Late-Career Surge of Mihaela Buzarnescu

The newest member of the WTA top 32 got there the hard way. Mihaela Buzarnescu, who achieved her latest career-high ranking with a run to the final of last week’s Prague event, where she lost a three-setter to Petra Kvitova, made her professional debut 14 years ago. Despite a dose of junior success, including a junior doubles title at the 2006 US Open, she didn’t crack the top 100 until last October.

This isn’t how tennis career trajectories are supposed to work. Yes, the game is getting older and stars are extending their careers, but Buzarnescu’s year-long winning spree, in which she has climbed from outside the top 400 to inside the top 40, began after her 29th birthday. The closer we look at what the Romanian has achieved, and the age at which she’s doing so, the more unusual it appears.

The oldest top 100 debuts

Since the beginning of the 1987 season, 630 women have debuted in the top 100. Their average age, on the Monday they reached the ranking threshold, is just under 20 years and 6 months. Only 29 of the 630–less than five percent–broke into the top 100 after their 26th birthday.

Only 14 players did so after turning 27:

Player                 Debut  Age (Y)  Age (D)  Peak Rank  
Tzipi Obziler       20070219       33      306         75  
A. Villagran Reami  19880801       31      359         99  
Mihaela Buzarnescu  20171016       29      165         32  
Julie Ditty         20071105       28      305         89  
Eva Bes Ostariz     20010716       28      183         90  
Mashona Washington  20040719       28       49         50  
Maureen Drake       19990201       27      317         47  
Tatjana Maria       20150406       27      241         46  
Hana Sromova        20051107       27      211         87  
Laura Siegemund     20150914       27      193         27  
Flora Perfetti      19960708       27      160         54  
Louise Allen        19890227       27       51         83  
Kristina Barrois    20081020       27       20         57  
Iryna Bremond       20111017       27       11         93

Buzarnescu doesn’t quite top this list, but she is certainly a more consequential force on tour than either of the women who debuted at a more advanced age. Tzipi Obziler fought her way through the lower levels of the game for just as long as Buzarnescu did, though she never cracked the top 70. Adriana Villagran Reami played a limited schedule; she may have had the skills to play top-100 tennis long before the ranking table made it official, but she was never a tour regular.

The most comparable player to Buzarnescu is Laura Siegemund, who reached a double-digit ranking a few years ago, and has since climbed as high as No. 27. Of the oldest top-100 debutants, though, very few have continued to ascend the rankings as far as Buzarnescu and Siegemund have.

Here are the oldest top-100 debuts of players who went on to crack the top 32:

Player                      Debut  Age (Y)  Age (D)  Peak  
Mihaela Buzarnescu       20171016       29      165    32  
Laura Siegemund          20150914       27      193    27  
Sybille Bammer           20050822       25      117    19  
Shinobu Asagoe           20000710       24       12    21  
Manon Bollegraf          19880215       23      310    29  
Johanna Konta            20140623       23       37     4  
Anne Kremer              19981019       23        2    18  
Lesia Tsurenko           20120528       22      364    29  
Kveta Peschke            19980420       22      286    26  
Petra Cetkovska          20071022       22      256    25  
Tathiana Garbin          20000214       22      229    22  
Li Na                    20041004       22      221     2  
Mara Santangelo          20040202       22      219    27  
Ginger Helgeson Nielsen  19910325       22      192    29  
Casey Dellacqua          20070806       22      176    26

Here’s an indication of just how young women’s tennis is: The 9th-oldest top-100 debutant on this list achieved her feat before her 23rd birthday. Put another way: Of the 107 women to break into the top 100 after their 23rd birthday, only eight went on to a ranking of No. 32 or better. By comparison, about one-third of all top-100 players peak at a ranking in the top 32. In this category, Buzarnescu is charting entirely new territory.

Making up for lost time

The last six months or so have been a whirlwind for the Romanian, as she has gone from a fringe tour player that no one had ever heard of, to a solid tour regular that … well, most fans still don’t know much about. Many players need some time to adjust to the higher level of competition and spend months, even years, stagnating in the rankings. Buzarnescu, on the other hand, has barely stopped to take a breath.

It took 203 days from her top-100 debut last October to her latest career-high at No. 32 on Monday. Siegmund, by comparison, needed 315 days; Sybille Bammer took 574 days; Roberta Vinci, who eventually cracked the top ten, required 2,520 days, or nearly seven years. The average player who reaches the top 32 needs two and a half years between her first appearance in the top 100 and clearing the higher bar.

Buzarnescu’s climb doesn’t fit the mold of older debuts. Her climb has more in common with those of teenage sensations. Again since 1987, here are the 20 quickest ascents:

Player              Age (Y)  Age (D)  Peak  Ascent Days  
Jennifer Capriati        14       11     1            0  
Anke Huber               15      266     4           49  
Agnes Szavay             18      164    13           77  
Lindsay Davenport        16      238     1          112  
Naoko Sawamatsu          17       31    14          119  
Clarisa Fernandez        20      265    26          133  
Maria Sharapova          16       58     1          133  
Serena Williams          16       52     1          133  
Miriam Oremans           20      145    25          140  
Venus Williams           16      301     1          147  
Sofia Arvidsson          21      223    29          154  
Leila Meskhi             19      308    12          168  
Tatiana Golovin          16       22    12          175  
Eugenie Bouchard         19       42     5          189  
Martina Hingis           14       31     1          189  
Ana Ivanovic             16      361     1          196  
Conchita Martinez        16      107     2          196  
Mihaela Buzarnescu       29      165    32          203  
Darya Kasatkina          18      137    11          203  
Ashleigh Barty           20      316    16          210

The player Buzarnescu knocked out of the top 20: Kim Clijsters. She is the only woman on the list to have cracked the top 100 after her 22nd birthday, yet here she is, climbing from No. 101 to No. 32 in less time than 92% of her peers.

Common sense suggests that Buzarnescu can climb only so much higher: Most players don’t set new career highs in their 30s, especially those who have such a short track record of tour-level success. On the other hand, she has adapted quickly, recording her first top ten win, over Jelena Ostapenko, in February and taking a set from Kvitova in Saturday’s final.

What’s more, she’ll reap the benefits of seeds at many events, probably including Roland Garros and Wimbledon. Having proven that she can defeat top 50 players–she holds a 6-7 career record against them–her new status as a top-32 player means she’ll get plenty of opportunities to rack up points against a less-daunting brand of competition. After more a decade of fighting steeply uphill battles, she has finally–improbably–earned a place among the game’s elite. Now all she has to do is keep winning.

The Men Are Old, and The Best Men Are Even Older

Italian translation at settesei.it

It’s been one of the main talking points in men’s tennis for years now: The sport is getting older. Every year, a bigger slice of Grand Slam draws are taken up by thirty-somethings, and now, the entire big four has entered their fourth decades.

I don’t want to belabor the point. But my interest was piqued by an observation from commentator Chris Fowler this week:

When we talk about the sport getting older, this is what we really mean — the best guys are getting up in years.

When we calculate the average age of a draw, or the number of 30-somethings, we weight every player equally. Democratic as it is, it gives most of the weight to guys who are looking for flights home before middle Sunday. As substantial as the overall age shift has been over the last decade, the shift at the top of the game has been even more dramatic.

To quantify the shift, I calculated what I’ll call the “projected winner age” (PWA) of every Wimbledon men’s field from 1991 to 2017. This captures in one number the notion that Fowler is hinting at. We take a weighted average of all 128 men in the main draw, weighted by their chances of winning the tournament, as determined by grass-court Elos at the start of the event.

For example, last year’s Wimbledon men’s draw had an average age of 28.5 years, but a projected winner age of 30.0. We don’t yet know the exact average age of this year’s draw (it looks to be about the same, maybe a tiny bit younger), but we can already say that the PWA is 31.4.

An observer a decade ago would’ve thought such a number was insane. Here are the average ages and PWAs for the last 27 Wimbledons men’s events:

As recently as 2011, there wasn’t much difference between average age and PWA. Until 2015, the difference had never been greater than two years. Now, the difference is almost three years, and the point of comparison–average age–is nearly its own all-time high.

A lot of this, of course, is thanks to the big four. Even as the aging curve has shifted, allowing for late bloomers such as Stan Wawrinka, the biggest stars of the late ’00s–Roger Federer and Rafael Nadal–have declined even less than the revised aging curve would imply. In a sport hungry for new winners, we might have to settle for winners who are newly in their 30s.

Is Jelena Ostapenko More Than the Next Iva Majoli?

Italian translation at settesei.it

Winning a Grand Slam as a teenager–or, in the case of this year’s French Open champion Jelena Ostapenko, a just-barely 20-year-old–is an impressive feat. But it isn’t always a guarantee of future greatness. Plenty of all-time greats launched their careers with Slam titles at age 20 or later, but three of the players who won their debut major at ages closest to Ostapenko’s serve as cautionary tales in the opposite direction: Iva Majoli, Mary Pierce, and Gabriela Sabatini. Each of these women was within three months of her 20th birthday when she won her first title, and of the three, only Pierce ever won another.

However, simply comparing her age to that of previous champions understates the Latvian’s achievement. Women’s tennis has gotten older over the last two decades: The average age of a women’s singles entrant in Paris this year was 25.6, a few days short of the record established at Roland Garros and Wimbledon last year. That’s two years older than the average player 15 years ago, and four years older than the typical entrant three decades ago. Headed into the French Open this year, there were only five teenagers ranked in the top 100; at the end of 2004, the year of Maria Sharapova’s and Svetlana Kuznetsova’s first major victories, there were nearly three times as many.

Thus, it doesn’t seem quite right to group Ostapenko with previous 19- and 20-year-old first-time winners. Instead, we might consider the Latvian’s “relative age”—the difference between her and the average player in the draw—of 5.68 years younger than the field. When I introduced the concept of relative age last week, it was in the context of Slam semifinalists, and in every era, there have been some very young players reaching the final four who burned out just as quickly. The same isn’t true of women who went on to win major titles.

In the last thirty years, only two players have won a major with a greater relative age than Ostapenko: Sharapova, who was 6.66 years younger than the 2004 US Open field, and Martina Hingis, who won three-quarters of the Grand Slam in 1997 at age 16, between 6.3 and 6.6 years younger than each tournament’s average entrant. The rest of the top five emphasizes Ostapenko’s elite company, including Monica Seles (5.29, at the 1990 French Open) and Serena Williams (5.26, at the 1999 US Open).

Each of those four women went on to reach the No. 1 ranking and win at least five majors–an outrageously optimistic forecast for Ostapenko, who, even after winning Roland Garros, is ranked outside the top ten. By relative age, Majoli, Pierce, and Sabatini are poor comparisons for Saturday’s champion–Majoli and Pierce were only three years younger than the fields they overcame, and Sabatini was only two years younger than the average entrant. By comparison, Garbine Muguruza, who won last year’s French Open at age 22, was two and a half years younger than the field.

Which is it, then? Unfortunately I don’t have the answer to that, and we probably won’t have a better idea for several more years. For most of the Open Era, until about ten years ago, the average age on the women’s tour fluctuated between 21 and 23. Thus, for the overall population of first-time major champions, actual age and relative age are very highly correlated. It’s only with the last decade’s worth of debut winners that the numbers meaningfully diverge. For Ostapenko and Muguruza–and perhaps Victoria Azarenka and Petra Kvitova–we have yet to see what their entire career trajectory will look like. To build a bigger sample to test the hypothesis, we’ll need a few more young first-time Slam winners, something we may finally see with Sharapova and Williams out of the way.

For more post-French Open analysis, here’s my Economist piece on Ostapenko and projecting major winners in the long term. Also at the Game Theory blog, I wrote about Rafael Nadal and his abssurd dominance on clay in a fast-court-friendly era.

Finally, check out Carl Bialik’s and my extra-long podcast, recorded Monday, with tons of thoughts and the winners and the fields in general.

Jelena Ostapenko and Teenage Slam Breakthroughs

Italian translation at settesei.it

Jelena Ostepenko is looking ahead to a big day on Thursday: She’ll celebrate her 20th birthday by playing her first Grand Slam semifinal.

A generation or two ago, a breakthrough accomplishment at age 20 would barely merit acknowledgement. In the late 1990s, women’s tennis was dominated by teens a recent teens: Serena Williams and Martina Hingis both won majors before their 20th birthday, and Venus Williams won her first Slam only a few days into her third decade. That youth brigade wasn’t just a couple of once-in-a-generation talents, either: 19-year-old Iva Majoli won a major, and Mirjana Lucic, Jelena Dokic, and Anna Kournikova all reached semifinals before their 18th birthdays.

Times have changed. The last teenage Slam champion was Maria Sharapova in 2006, and we haven’t had a teenager in a major final since Caroline Wozniacki in 2009. Since then, only four players–Ostapenko, Sloane Stephens, Eugenie Bouchard, and Madison Keys–have reached Grand Slam semifinals before their 20th birthdays. (To simplify matters, I’m defining tournament age as age at the beginning of the event, so Ostapenko is a 19-year-old for the purpose of this discussion.)

By just about any measure you can dream up, the sport is getting older. In 1990, the average age of the women in the French Open main draw was 21.8 years. In 2000, it was 23.5. This year, the average age at the start of the tournament was 25.6, just a tiny bit short of last year’s record–set at Roland Garros and Wimbledon–of 25.7. Veterans are sticking around longer, and it takes longer for young players to develop tour-ready games.

Accordingly, we need to revise our notion of what constitutes a big breakthrough. 20 years ago, the semifinal debut of a 19-year-old was a nice achievement for the player herself, but nothing earth-shaking. Today, it’s a once-in-two-years event, and immediately puts the debutante in elite company. While Stephens and Bouchard have stumbled since their own breakthroughs, they (along with Keys) are still among the most promising young players in the game.

To quantify Ostapenko’s achievement, let’s consider her age relative to the average of all main draw players–just the raw difference between those two numbers. Ostapenko is 5.68 years younger than the average woman at Roland Garros this year, making her the 7th youngest (relative to the field) semifinalist at a major since 2000:

Slam     Youngest SF         Age  Avg Age  Diff  
2004 W   Maria Sharapova   17.17    24.17  7.00  
2006 FO  Nicole Vaidisova  17.10    23.63  6.53  
2000 W   Jelena Dokic      17.21    23.69  6.48  
2005 W   Maria Sharapova   18.17    24.45  6.28  
2005 AO  Maria Sharapova   17.75    23.99  6.24  
2007 AO  Nicole Vaidisova  17.73    23.48  5.75  
2017 FO  Jelena Ostapenko  19.97    25.65  5.68  
2001 FO  Kim Clijsters     17.97    23.62  5.65  
2005 US  Maria Sharapova   18.36    23.78  5.42  
2015 AO  Madison Keys      19.92    25.33  5.41

Only three players–Sharapova, Dokic, and Nicole Vaidisova–have reached a Slam semifinal this century at such a young age compared to the rest of the draw.

Of course, names like Dokic and Vaidisova aren’t the most encouraging comparisons for an emerging star. Both players peaked in the top ten, but neither ever reached a major final. The WTA’s past is littered with teenage rising stars who ultimately fizzled.

Yet if we are to see one historically great player come from among today’s young players, she should start building her trophy collection now. It’s tough to put together a Hall of Fame-caliber career without winning some big titles by one’s early 20s. Madison Keys has put herself in that conversation, and this week, Ostapenko has done so as well.

The Case for Novak Djokovic … and Roger Federer … and Rafael Nadal

Italian translation at settesei.it

By winning the US Open last weekend and increasing his career total to ten Grand Slams, Novak Djokovic has pushed himself even further into conversations about the greatest of all time. At the very least, his 2015 season is shaping up to be one of the best in tennis history.

A recent FiveThirtyEight article introduced Elo ratings into the debate, showing that Djokovic’s career peak–achieved earlier this year at the French Open–is the highest of anyone’s, just above 2007 Roger Federer and 1980 Bjorn Borg. In implementing my own Elo ratings, I’ve discovered just how close those peaks are.

Here are my results for the top 15 peaks of all time [1]:

Player                 Year   Elo  
Novak Djokovic         2015  2525  
Roger Federer          2007  2524  
Bjorn Borg             1980  2519  
John McEnroe           1985  2496  
Rafael Nadal           2013  2489  
Ivan Lendl             1986  2458  
Andy Murray            2009  2388  
Jimmy Connors          1979  2384  
Boris Becker           1990  2383  
Pete Sampras           1994  2376  
Andre Agassi           1995  2355  
Mats Wilander          1984  2355  
Juan Martin del Potro  2009  2352  
Stefan Edberg          1988  2346  
Guillermo Vilas        1978  2325

A one-point gap is effectively nothing: It means that peak Djokovic would have a 50.1% chance of beating peak Federer. The 35-point gap separating Novak from peak Rafael Nadal is considerably more meaningful, implying that the better player has a 55% chance of winning.

Surface-specific Elo

If we limit our scope to hard-court matches, Djokovic is still a very strong contender, but Fed’s 2007 peak is clearly the best of all time:

Player          Year  Hard Ct Elo  
Roger Federer   2007         2453  
Novak Djokovic  2014         2418  
Ivan Lendl      1989         2370  
Pete Sampras    1997         2356  
Rafael Nadal    2014         2342  
John McEnroe    1986         2332  
Andy Murray     2009         2330  
Andre Agassi    1995         2326  
Stefan Edberg   1987         2285  
Lleyton Hewitt  2002         2262

Ivan Lendl and Pete Sampras make much better showings on this list than on the overall ranking. Still, they are far behind Fed and Novak–the roughly 100-point difference between peak Fed and peak Pete is equivalent to a 64% probability that the higher-rated player would win.

On clay, I’ll give you three guesses who tops the list–and your first two guesses don’t count. It isn’t even close:

Player           Year  Clay Ct Elo  
Rafael Nadal     2009         2550  
Bjorn Borg       1982         2475  
Novak Djokovic   2015         2421  
Ivan Lendl       1988         2408  
Mats Wilander    1984         2386  
Roger Federer    2009         2343  
Jose Luis Clerc  1981         2318  
Guillermo Vilas  1982         2316  
Thomas Muster    1996         2313  
Jimmy Connors    1980         2307

Borg was great, but Nadal is in another league entirely. Though Djokovic has pushed Nadal out of many greatest-of-all-time debates–at least for the time being–there’s little doubt that Rafa is the greatest clay court player of all time, and likely the most dominant player in tennis history on any single surface.

Djokovic is well back of both Nadal and Borg, but in his favor, he’s the only player ranked in the top three for both major surfaces.

The survivor

As the second graph in the 538 article shows, Federer stands out as the greatest player of all time at his age. Most players have retired long before their 34th birthday, and even those who stick around aren’t usually contesting Grand Slam finals. In fact, Federer’s Elo rating of 2393 after his US Open semifinal win against Stanislas Wawrinka last week would rank as the sixth-highest peak of all time, behind Lendl and just ahead of Andy Murray.

Here are the top ten Elo peaks for players over 34:

Player         Age   34+ Elo  
Roger Federer  34.1     2393  
Jimmy Connors  34.1     2234  
Andre Agassi   35.3     2207  
Rod Laver      36.6     2207  
Ken Rosewall   37.4     2195  
Tommy Haas     35.3     2111  
Arthur Ashe    35.7     2107  
Ivan Lendl     34.1     2054  
Andres Gimeno  35.0     2035  
Mark Cox       34.0     2014

The 160-point gap between Federer and Jimmy Connors implies that 34-year-old Fed would win about 70% of the time against 34-year-old Connors. No one has ever sustained this level of play–or anything close to it–for this long.

At the risk of belaboring the point, similar arguments can be made for 33-year-old Fed, all the way to 30-year-old Fed. At almost any stage in the last four years, Federer has been better than any player in history at that age [2].  Djokovic has matched many of Roger’s career accomplishments so far, especially on clay, but it would be truly remarkable if he maintained a similar level of play through the end of the decade.

Current Elo ratings

While it’s not really germane to today’s subject, I’ve got the numbers, so let’s take a look at the current ATP Elo ratings. Since Elo is new to most tennis fans, I’ve included columns to indicate each player’s chances of beating Djokovic and of beating the current #10, Milos Raonic, based on their rating. As a general rule, a 100-point gap translates to a 64% chance of winning for the favorite, a 200-point gap implies 76%, and a 500-point gap is equivalent to 95%.

Rank  Player                  Elo  Vs #1  Vs #10  
1     Novak Djokovic         2511      -     91%  
2     Roger Federer          2386    33%     84%  
3     Andy Murray            2332    26%     79%  
4     Kei Nishikori          2256    19%     71%  
5     Rafael Nadal           2256    19%     71%  
6     Stan Wawrinka          2186    13%     62%  
7     David Ferrer           2159    12%     58%  
8     Tomas Berdych          2148    11%     56%  
9     Richard Gasquet        2128    10%     54%  
10    Milos Raonic           2103     9%       -  
                                                  
Rank  Player                  Elo  Vs #1  Vs #10  
11    Gael Monfils           2084     8%     47%  
12    Jo-Wilfried Tsonga     2083     8%     47%  
13    Marin Cilic            2081     8%     47%  
14    Kevin Anderson         2074     7%     46%  
15    John Isner             2035     6%     40%  
16    David Goffin           2027     6%     39%  
17    Grigor Dimitrov        2021     6%     38%  
18    Gilles Simon           2005     5%     36%  
19    Jack Sock              1994     5%     35%  
20    Roberto Bautista Agut  1986     5%     34%  
                                                  
Rank  Player                  Elo  Vs #1  Vs #10  
21    Philipp Kohlschreiber  1982     5%     33%  
22    Tommy Robredo          1963     4%     31%  
23    Feliciano Lopez        1955     4%     30%  
24    Nick Kyrgios           1951     4%     29%  
25    Ivo Karlovic           1949     4%     29%  
26    Jeremy Chardy          1940     4%     28%  
27    Alexandr Dolgopolov    1940     4%     28%  
28    Bernard Tomic          1936     4%     28%  
29    Fernando Verdasco      1932     3%     27%  
30    Fabio Fognini          1925     3%     26%

Continue reading The Case for Novak Djokovic … and Roger Federer … and Rafael Nadal

The Dream of the Nineties is Alive

Italian translation at settesei.it

Last weekend, the four finalists in ATP events were David Goffin, Dominic Thiem, Vasek Pospisil, and Milos Raonic. All were born in the 1990s, making the Kitzbuhel and Washington finals the first all-nineties championship matches in tour history.

It’s about time. The first half of the 1990-born cohort is already 24 years old, an age that used to suggest a tennis player was approaching his prime. Of the four finalists, only Thiem wasn’t born in 1990. (He was born in 1993, making him the youngest finalist of the season so far.)

It has never taken so long for a single-year-or-younger group of ATP players to play each other in a final. For the thirty-one years between 1960 births and 1990 births, it has, on average, taken less than 21 years before youngsters in each cohort face off for a title. It took 24 years and seven months before the 1990 group–with the help of Thiem–finally reached this milestone.

Here are the breakthrough finals for each age group in five-year intervals, to put the 1990 group in perspective:

The age of these milestone finals has been steadily creeping up over the last few years. The class of 1987 was a good one, giving us Novak Djokovic and Andy Murray, but even those two stars didn’t meet in a final until the 2008 Cincinnati Masters, when both had passed their 21st birthdays.

There’s a sharp downturn after that 1987 class. The ATP didn’t see a 1988-or-younger final until three years later, when Alexandr Dolgopolov faced Marin Cilic in the 2011 Umag title match. In the three years since then, there have been only six more 1988-or-younger finals, including the two last weekend.

Thiem, along with a few other young players, offers hope that the tides are beginning to turn. This week, for the first time since 2005 (when, as we’ve seen, Nadal and Berdych played the last all-teenage final), the ATP top 200 features four teenagers, two of whom–Borna Coric and Alexander Zverev–are not yet 18. Then again, neither Goffin nor Pospisil reached a final until they had been inside the top 200 for three years. We may need to keep looking to 23-year-olds for ATP firsts.

Nick Kyrgios and the First Fifty Matches

Italian translation at settesei.it

When Nick Kyrgios lost the Wimbledon quarterfinal to Milos Raonic yesterday, he was playing his 50th career match at the Challenger level or above. Round numbers invite big-picture analysis, so let’s see how Kyrgios stacks up to the competition at this early milestone.

When Monday’s rankings are released, Nick will debut in the top 100, all way up to #66. Only Rafael Nadal (61), Gael Monfils (65), and Lleyton Hewitt (65) have been ranked higher at the time of their 51th Challenger-or-higher match.  Roger Federer was #93, Novak Djokovic was #128, and Jo Wilfried Tsonga was #314. Of the current top 100, only ten players reached a double-digit ranking by their 51st match.

The wealth of ranking points available at Grand Slams have played a big part in Kyrgios’s rise, but they don’t tell the whole story. He has won 36 of his first 50 matches, equal to the best of today’s top 100. Nadal went 36-14, and next on the list is Djokovic and Santiago Giraldo (who played almost all Challengers) at 34-16. Most of Nick’s wins before this week came at Challengers, and he has won four titles at the level.

No other active player won four Challenger titles in his first 50 matches. Eight others, including Djokovic, Tsonga, Stanislas Wawrinka, and David Ferrer, won three. All of them needed more events at the level to win three titles than Kyrgios did to win four.

Nick’s short Challenger career is another indicator of a bright future. He has only played nine Challenger events, and with his ranking in the 60s, he may never have to play one again. As I’ve previously written, the best players tend to race through this level: Federer, Nadal, and Djokovic all played between eight and twelve Challengers. It’s a rare prospect that makes the jump in fewer than 20 events, and when I researched that post two years ago, more than half of the top 100 had played at least 50 Challengers.

One category in which the Australian doesn’t particularly stand out is age. When he plays his 51st match, he’ll a couple of months past his 19th birthday. Roughly one-quarter of the current top 100 reached that match total at an earlier age. Nadal, Richard Gasquet, and Juan Martin del Potro did so before their 18th birthday, while Djokovic, Hewitt, and Bernard Tomic needed only a few more weeks beyond that.

Without knowing how Kyrgios would’ve performed on tour a year or two earlier, it’s tough to draw any conclusions. His 36-14 record at 19 certainly isn’t as impressive as Rafa’s equivalent record at 17.

Cracking the top 100 at 17 or 18 is a much better predictor of future greatness than doing so at 19, but as the tour ages, 19 may be the new 16. Grigor Dimitrov didn’t enter the top 100 until he was three months short of his 20th birthday, while Dominic Thiem and Jiri Vesely were still outside the top 100 on their 20th birthdays. Among his immediate cohort, Kyrgios stands alone: No other teenager is ranked within the top 240.

As predictive measures go, Nick’s Wimbledon performance–built on his poise under pressure–is the best sign of them all. Only seven active players have reached a Grand Slam quarterfinal as a teenager, and four of them–Fed, Rafa, Novak, and Lleyton–went on to reach #1. (The other three are Delpo, Tomic, and Ernests Gulbis.)

For a player with only fifty matches under his belt, that’s excellent company.

Teenagers, Thirty-Somethings, and Americans at Grand Slams

I’ve put together a few reports showing how age distributions and US presence have changed over the years at Grand Slams.  Let’s start with player age.

The average age of players in the Wimbledon men’s singles draw is 27.7 years, which is just short of the all-time record, 27.8, set at Roland Garros last month, and equal to last year’s figure at Wimbledon. There are two teens in the draw (up one from last year), and 34 thirty-somethings, which is tied for third-most since 1982.

This report shows the complete year-by-year breakdown for the last 30 years’ worth of men’s slam draws.

The average age in the Wimbledon women’s draw is also very high by historical standards.  At 25.2 years, it’s tied with this year’s French Open and 2012 Wimbledon for the highest ever.  43-year-old Kimiko Date Krumm moves the needle all by herself; without her, the average would be 25.0, still considerably higher than any other pre-2010 slam.

There are ten teenagers in the draw, which is very low for the WTA, but safely above the all-time low of 7, set at Wimbledon two years ago. The total of 16 players aged 30 or over is good for third-most of all time, behind this year’s and last year’s French Opens.

Here’s the WTA report showing these numbers for each slam in the last 30 years.

(All of the figures above for 2014 Wimbledon could change slightly if more lucky losers are added to the draw.)

I also put together a couple of reports showing the number of Americans in each slam draw, broken down by direct entrants, qualifiers, lucky losers, and wild cards, along with the top seed, the number of seeds (and top 16 seeds), plus the number of Americans in each round:

Enjoy!