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.