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Unlike the men’s side, which has seen only three unique champions in the last decade at the Australian Open, the women’s tour has had eight different players raise trophies in Melbourne. Likewise, of the past 19 Slams, there have been 14 unique winners, compared to only five for the ATP. Every year since 2016 has seen unique champions at each of the four women’s Slams. The last time there was a distinct winner at each Slam event of the year for the men: 2003. All of these quick facts illustrate that the women’s draw in a major always promises tons of excitement and upsets, and this year’s Australian Open is no different.
As the action gets underway Down Under, there is the mix of traditional favorites, along with aspiring first-time champions. World No. 1 and Australian Ashleigh Barty would love to win a Slam in front of her home crowd. Naomi Osaka returns as the defending champion. Teenage phenoms like Coco Gauff, Emma Raducanu and Leylah Fernandez are still breaking onto the scene. Amid the unpredictability of the women’s side, we attempted to forecast a winner, simulating the tournament to find estimated probabilities for every single player in the draw to not only reach any given round but also to win it all.
Trying to predict outcomes with probabilities is common in sports, but the challenges of doing so for a Grand Slam tennis tournament with a draw size of 128 are daunting. This is because a lot of the probabilities are interdependent and can change meaningfully with each result, particularly unexpected ones. For example, if Barty were to lose in an earlier round in the draw (as unlikely as that might be), Osaka’s probability of winning would rise drastically, since she would no longer have to play Barty in the fourth round.
Nevertheless, we can still try to predict the outcome of the Australian Open through a simulation. For my simulation, I used Tennis Abstract’s Elo ratings, which can be adjusted for different surfaces. For example, Osaka ranks ninth overall in Elo but fourth on hard courts, her strongest surface. Now, with the actual draw, we can simulate the tournament thousands of times using Elo ratings to see the different potential outcomes. For instance, if Barty wins the simulation 3,000 out of 10,000 times, she has approximately a 30% chance of winning. While there is seeding in tennis (No. 1-No. 32), the draw doesn’t rely purely on those rankings. In a Grand Slam, a No. 1 seed could play a No. 17 seed or a No. 32 seed in the third round. This creates possibilities for many interesting matchups throughout the tournament, with potential upsets besetting star players.
No Australian woman has won on home turf since Christine O’Neil in 1978. Long gone are the days when all-time Grand Slam leader Margaret Court would dominate (she won 11 of her 24 majors at the Aussie Open, some of which were before the Open Era). Already at age 25, there is no doubt that Barty is the best Australian player since Court, as she has finished with the top world ranking for the past three years and already ranks eighth all-time and second among active players in total weeks (110) at No. 1. The only critique of Barty is that she hasn’t converted her dominance into Slams, winning just two (2019 French Open and 2021 Wimbledon). Barty’s winning percentage at the majors (68%) is below her norm (73%). Compare that with her No. 1 counterpart on the men’s side, Novak Djokovic who wins 88% of Slam matches compared to 83% of others. Barty has fared well in her past three Australian Opens, making at least the quarterfinals, but she has never reached the finals. Fresh off a singles and doubles title at the warm-up tournament in Adelaide, Barty will look to make a deep run with the fans behind her. She does have one of the tougher paths to victory, potentially facing Osaka in the fourth round (split 2-2 in their career but haven’t played since 2019), but still has the highest overall probability at 17%.
Naomi Osaka enters the draw as the 13th seed but has the second highest Vegas odds behind Barty (+500 vs. +275). Osaka’s probability rank of ninth outperforms her seeding, thanks to her fourth overall Elo rating. Currently No. 14 in the world, Osaka is at her lowest rank since 2018, right before she won her first U.S. Open at age 20. Osaka has dropped off in part because of her struggles at the end of 2021, but more so because she took time off for mental health and she was not able to defend the points she had won from the prior year. After withdrawing from the French in the second round, she missed the rest of the summer circuit until right before the U.S. Open. Osaka just withdrew from the semifinals of the warm-up in Melbourne with an abdominal injury, which is likely just a precaution to make sure she is at full health for the main event. Though not a top seed, Osaka should still be one of the favorites to take home the title as hard courts are her best surface and the Australian Open is historically her best Grand Slam (85% winning percentage).
Anett Kontaveit will be a new name for many tennis fans, but they should definitely be on the lookout for a breakout performance from her. The Estonian has been on a tear lately, winning four titles in the second half of 2021 in Cleveland, Ostrava, the Kremlin Cup and the Transylvania Open, and reaching the finals of the WTA Year End Finals. In those four title runs, she dropped a mere three sets. The only factor working against Kontaveit is her lack of a successful track record at the Slams. She has only made the quarterfinals once (2020 Australian Open) despite 26 main draw Slam appearances. She has been ranked in the Top 30 since 2017 but took her biggest leap forward in 2021, and she now sits at a career high No. 7. This would be a late peak for Kontaveit at 26 years old, but with her recent results she ranks second in hard court Elo, giving her a 8% chance at the title.
Prior Slam Champions
Rather than Kontaveit, who is relatively unknown, more familiar names round out the list of the top competitors in the draw. The trio of Garbine Muguruza, Simona Halep, and Victoria Azarenka are all two-time Slam champions. There are reasons to pick each one of these veterans. The highest seed of the trio at No. 3, Muguruza arguably had the best end to the year, winning the Chicago Tennis Classic and the WTA Year End finals. Halep has probably had the best overall career, spending 64 weeks at No. 1. Since returning from injury, she made the finals of the Transylvania Open and just won a warm-up tournament in Melbourne. For two-time Aussie Open champion Azarenka, it is her most successful Slam (78% winning percentage), but she has not made it past the first round since 2016. The WTA rankings of No. 14 Halep and No. 24 Azarenka are below their probability ranking, since they didn’t play as many tournaments last year, missing time with injuries. If any of these three former Grand Slam champions and world No. 1s can regain some of their historic form, they have a shot at a deep run in Australia with a combined championship probability of 21%.
Teenage Upstarts: Coco Gauff, Emma Raducanu, Leylah Fernandez
A prominent narrative around women’s tennis has featured the emergence of teenagers. Still only 17, Coco Gauff is the American phenom, and fans are awaiting the day when she will become the highest-ranked American by overtaking Serena Williams and Sofia Kenin. She might be in a bit of a sophomore slump; her ranking has stagnated at her career high of No. 19 for the past six months. But she still has plenty of time to break through. Raducanu (age 19) stormed onto the scene last summer, reaching the fourth round of Wimbledon in her Grand Slam debut after receiving a wild card. She then did seemingly the impossible, winning the U.S. Open as a qualifier without dropping a set in 10 matches. Since that magical run she has only won two matches in four tournaments and faces a tough first round match against American U.S. Open champion Sloane Stephens. Leylah Fernandez, who Raducanu faced in the U.S. Open final, is also entered in the field and is seeking her first Australian Open match victory but has the highest championship odds of the young trio.
As the first Grand Slam, the Australian Open always kicks off the year with the potential for new stars to break out after the offseason. Whether it’s a home crowd favorite (Barty), a former two-time Slam Champion (Osaka, Halep, Azarenka, Muguruza), or a teenager, the final champion who lifts the trophy will be one for the books.
David Arkow is an economics major and a member of the Harvard men’s varsity tennis team. This article is part of Sportico’s partnership with The Harvard Sports Analysis Collective, a student-run organization dedicated to the quantitative analysis of sports strategy and management.