The top of the all-time men’s grand slam ranking just got even more crowded. With his 13th Roland Garros title, Rafael Nadal has matched Roger Federer at the top of the list by securing his 20th major title. Novak Djokovic, Nadal’s final obstacle en route to the historic mark, remains within shouting distance with 17 slams.
The Roger-Rafa tie has spurred another (interminable, unresolvable) round of the (interminable, unresolvable) GOAT debate. Of course there’s much more to determining the best ever than the slam count. But the slam count is a big part of the conversation. If we’re going to keep doing this, we ought to at least recognize that not all major titles are created equal. And by extension, not all collections of twenty major titles are equivalent.
We all have intuitions about the difficulty of how a particular draw shakes out, with its typical mix of good and bad fortune. Nadal was lucky that he missed a few dangerous opponents in the early rounds, luckier still that he didn’t have to face Dominic Thiem in the semi-final, and unfortunate that he had to face down the next-best player in the draw, Djokovic, in the final. As it turned out, it didn’t really matter, but I think most of us would agree that Nadal’s achievement–staggering as it is–would look even better had he faced more than two more players ranked in the top 70.
Stop dithering and start calculating
I’ve written about this before, and I’ve established a metric to quantify those intuitions. Take the surface-weighted Elo rating of each of a player’s opponents, and determine the probability that an average slam champion would beat those players. After a couple of steps to normalize the results, we end up with a single number for the path to each slam title. The larger the result, the more difficult the path, and an average slam works out to 1.0.
Nadal’s path was easier than the historical average. Aside from Djokovic, none of his opponents would have had more than an 8% chance of knocking out an average slam champion on clay. The exact result is 0.64, which is easier than almost nine-tenths of majors in the Open Era. Rafa has had three easier paths to his major titles, including the 2017 US Open, which scored only 0.33. That’s the easiest US Open, Wimbledon, or Roland Garros in a half-century.
Of course, he’s had his share of difficult paths, such as 2012 Roland Garros (1.36), when he faced several clay specialists and a peak-level Djokovic. Federer and Djokovic have gotten their own shares of lucky and unlucky draws over the years–that’s why we need a metric. You might have a better memory for this kind of thing than I do, but I don’t think any of us can weigh 57 majors with 7 opponents each and work out any meaningful results in our heads.
The tally
Sum up the difficulty of the title paths for these 57 slams, and here are the results:
Player Slams Avg Score Total
Nadal 20 0.95 19.0
Djokovic 17 1.06 18.1
Federer 20 0.89 17.9
Player Easy Medium Hard
Nadal 7 8 5
Djokovic 5 5 7
Federer 9 10 1
The first table shows each player’s average score for the paths to his major titles, and the total number of “adjusted slams” that gives them. Nadal is in the lead with 19, and Djokovic and Federer follow in a near-tie, just above and below 18.
You might be surprised to see the implication that this is a slightly weak era, with average scores a bit below 1.0. That wasn’t the case a few years ago, but there has only been one above-average title path since 2016. The Big Three-or-Four has generally stayed out of each other’s way since then, and even when they do clash, as they did yesterday, the leading contenders for quarter-final or semi-final challenges failed to make it that far. The average score of the last 15 slam title paths is a mere 0.73, while the 16 before that (spanning 2013-16) averaged 1.20.
The second table paints with a broader brush, classifying all Open Era slam titles into thirds: “easy,” “medium” and “hard” paths to the championship. Anything below 0.89 rates as “easy,” anything above 1.14 is marked as “hard,” with the remainder left as “medium.”
Djokovic is the leader in hard slams, with 7 of his 17 meriting that classification. Federer has racked up 10 medium slams, including several that score above 1.0, but only one that cleared the bar for the “hard” category. Nadal’s mix is more balanced.
Go yell at someone else
Hopefully these numbers have given you some new ammunition for your next twitter fight. Some of you will froth at the mouth while insisting that players can’t control who they play. You’re right, but it doesn’t really matter. We can’t start giving out GOAT points for things that players didn’t do, like beat Thiem in the 2020 French Open semi-finals. All three of these guys were or are good enough at various points to have beaten some of the opponents they didn’t have to face. There are other approaches we could take to the GOAT debate that incorporate peak Elo ratings and longevity at various levels, but that’s not what we’re talking about when we count slams.
If we are going to focus so much on the slam count, we might as well acknowledge that Nadal’s 20 is better than Federer’s 20, and Djokovic’s 17 is awfully close to both of them.