won her first Grand Slam title, defeating Garbiñe Muguruza in the final, 4–6, 6–2, 6–2. Kenin became the first American woman, other than Serena Williams, to win the Australian Open women's singles title since Jennifer Capriati in 2002. Kenin was the youngest Australian Open finalist since Ana Ivanovic and the youngest champion since Maria Sharapova, both in 2008. Muguruza was the first unseeded player, without being awarded a wildcard or entering through a protected ranking, to reach the Australian Open final since Williams in 2007. This was the first Australian Open final in the Open Era to be contested between two players ranked outside the top ten, and the first Grand Slam final to feature two players outside the top ten since the 2018 US Open final. Naomi Osaka was the defending champion, but lost to Coco Gauff in the third round. This was the final tournament for the 2018 champion and former world no. 1 Caroline Wozniacki, who announced her retirement effective at the end of the tournament. She lost in the third round to Ons Jabeur. This tournament was also the last event in which five-time Grand Slam champion, 2008 champion, and former World No. 1 Sharapova competed, losing to Donna Vekić in the first round. She announced her immediate retirement from professional tennis in February. Bianca Andreescu, the reigning women's singles champion of the 2019 US Open, the Grand Slam tournament immediately preceding the 2020 Australian Open, withdrew due to a knee injury. This marked the first time since the 1996 Australian Open that the defending US Open champion withdrew before the tournament. The elimination of Angelique Kerber in the fourth round guaranteed a new Australian Open champion. Jabeur became the first Arabian woman to reach the quarterfinals of a Grand Slam tournament, as well as the first African woman to reach the quarterfinals of a Grand Slam since Amanda Coetzer at the 2001 Australian Open. Ashleigh Barty became the first Australian woman to reach the women's singles semifinals since Wendy Turnbull in 1984. Barty's quarterfinal win over Petra Kvitová was her first ever top ten singles win at a Grand Slam. She had lost her five previous matches. Anett Kontaveit became the first player from Estonia, male or female, to reach the quarterfinals of the Australian Open. She would lose to Simona Halep in straight sets.
