World number 45 Ajla Tomljanovic has defeated Serena Williams 2-1 to advance to the fourth round of the US Open. Tomljanovic of Australia won the third stage match that lasted three hours and five minutes with sets of 7-5, 6-7, 6-1 at Arthur Ashe Stadium. With this victory, the Australian player qualified for the fourth round of the US Open for the first time. Williams, who ranked 413th in the world, has won 23 Grand Slam titles, including six US Open, in women's singles. Coco Gauff, Caroline Garcia, Alison Riske-Amritraj, and Liudmila Samsonova advanced to the next stage after beating their opponents. In the men's singles, reigning champion Daniil Medvedev defeated Wu Yibing in straight sets, 3-0, and moved to the fourth round. Casper Ruud, Pablo Carreno Busta, Nick Kyrgios, Karen Khachanov, and Corentin Moutet qualified for the Round of 16 in New York.