Some of the Most Surprising Runs in Recent Grand Slam History

With so much time these days to walk down tennis memory lane, I thought it would be fun to rank the wildest runs at the Grand Slams. In this post, I show how we can use the total gain in player ratings over an event to identify surprising individual results at the majors from the 1990s to the present.

One of the cool things about probabilistic rating systems like Elo is that they come with their own surprise tracker. With every result comes an update to a player’s rating and that update is essentially a weighted measure of surprise about the result. When Kevin Anderson defeated Roger Federer at the 2018 Wimbledon, his pre-match chance for the win was just 1 in 5. So that win was a real surprise and Anderson got a bigger boost in his player rating as a result. Rating systems are making these calculations with every player and every match result, producing an almost continuous barometer of surprise we can tap into.

These jumps in response to surprising results are all part of the self-correcting process of Elo-like rating systems. Now, any system that is doing a reasonable job of rating players shouldn’t be surprised a lot of the time. But there will be the occasion when a player has a win that just stumps the system. Think Lukas Rosol taking out Rafael Nadal at the 2012 Wimbledon.

Wins like that rarely happen multiple times in a row. If they do, it means something extraordinary has likely happened.

We can try to hone in on those occasions by looking at the total gain in rating points1 at an event, from the first to last match played. Using my historical ratings, which currently go back to 1990 for the men and 1997 for the women, I found that gains of 160 points or more represented the Top 5% of better-than-expected results at Grand Slams. Those top five percenters are what I’ll focus on below.

Over the period considered, only two men had a Grand Slam run that added more than 200 points to their rating at the start of the tournament. The biggest single gain was earned by Gustavo Kuerten with his maiden slam title at the 1997 French Open. The unseeded Brazilian shocked everyone that summer at Roland Garros. In fact, even with the points Kuerten gained with each round, he was still the underdog for all but one of his matches. Oddly enough it was his semifinal, where he met qualifier Filip Dewulf, that was his easiest match on paper.

The second spot goes to Andriy Medvedev (no relation that I could find to Daniel Medvedev) who reached the final of the 1999 French Open, what turned out to be the best single result of his career. By that year, Medvedev had already lost 5 times to the eventual champion of Roland Garros. After the sixth loss, when he went down in 5 sets to Andre Agassi, we have to wonder whether Medvedev lost his will for a major title.

Figure 1. Top 5% of most surprising Grand Slam runs for the ATP from 1993-2020 based on total event gain in rating points

Before Nadal’s reign at the event, I’ve long had the impression that the French Open has had more “weird” results than the other Grand Slams. I think there is some support for that in these results. Not only are the two most surprising results ones that happened on clay, but 8 of the 23 in the top 5% were runs at Paris.

Nadal put a stop to that trend from 2005 to 2013. Still, I was fascinated to find Nadal’s title win in 2014 make the list. Although Nadal earned nearly no points for his wins in the first four rounds, his victories over David Ferrer, Andy Murray, and Novak Djokovic (who had a higher overall rating at that time) were difficult enough to give him a total 166 point gain in his pre-event rating.

There are a number of results of the biggest names in the sport that make the list. You might expect all of those to be first slam wins, but not so. There is Pete Sampras’s final slam title at the 2002 US Open after a two-year drought at the majors. It is a similar story for Novak Djokovic’s win at the 2018 Wimbledon, which capped his first major win after achieving a career Grand Slam in 2016. Andre Agassi and Roger Federer also make the list at different resurgences in their career.

As sometimes happens, missing data tells as interesting a story as what is observed. For the surprise results at Grand Slams, the missing data is the long stretch between Rainer Schuettler reaching the semifinal at the 2008 Wimbledon to Rafael Nadal’s 2014 title at the French. Only Juan Martin Del Potro broke the streak of titles at Grand Slams during that period, giving us the longest stretch of consistent results at the majors during these years.

My final note on these results is the bizarre story of Vladimir Voltchkov. In 2000, Voltchkov, a talented junior player with few pro accolades, entered Wimbledon with a rating just over 1600. Bolstered by Ridley Scott’s testosterone-fueled take on Roman epic, The Gladiator, Voltchkov amazingly survived his first five opponents only to be rightfully dispatched by Pete Sampras in Voltchkov’s one and only major semifinal.

My historical ratings sadly don’t have as long a period for the women. But even from the results in the 2000s it is clear that the surprising runs have followed a starkly different pattern compared to the men. First, only one result at the French Open makes the list, this was twenty year-old Jelena Ostapenko’s title win in 2017, where she became the first player since Kuerten to earn her first career title at a Grand Slam.

The majority of recent surprise runs for the WTA have happened at the Australian Open (8 of the 22 shown). The most surprising of the Australian Open wins was Serena Williams' 2007 title, which she claimed after an injury-ridden 2006 season that caused her to miss most of the calendar and saw her ranking drop to as low as 139.

Figure 2. Top 5% of most surprising Grand Slam runs for the WTA from 1999-2020 based on total event gain in rating points

It is fitting that only Kim Clijsters’s comeback in 2009 could top Serena’s when it comes to surprise. Clijsters and Williams are the only two players who have so masterfully balanced motherhood and competition at different times in their career. While many thought Serena would win a Grand Slam within weeks of her return after childbirth, Clijsters remains the only player to have accomplished that feat. There was a good chance that one of the Williams sisters would have kept Clijsters from that miraculous run, Clijsters having just a 1 in 10 chance when she met Venus in the R16 and Serena in the semifinal. By the end of her journey in her first month back, Clijsters had another major title and added 300 points to her player rating, making it the most unexpected slam win in the past three decades.

  1. Using my Elo margin of victory player ratings ↩︎