World number two Elena Rybakina began her US Open campaign with a comfortable straight-sets win, easing past 17-year-old wildcard Thea Frodin 6-3 6-2 in her first match since retiring injured from her Cincinnati Masters quarter-final with a heel problem. The victory keeps alive Rybakina's chances of becoming world number one for the first time, with the 27-year-old trailing leader Aryna Sabalenka by just 434 ranking points heading into the tournament, and matters because it shows she has recovered fitness in time to mount a serious title and ranking challenge in New York.

Rybakina would rise to top spot by reaching the semi-finals regardless of Sabalenka's result, or automatically if none of Sabalenka, Coco Gauff or Jessica Pegula win the title. She dropped serve only once in the match, saving three match points against Frodin, the world number 585 and a former on-screen body double for Serena Williams, before closing out victory with her tour-leading 363rd ace of the season. Elsewhere at the tournament, Serena and Venus Williams, playing doubles together at a Grand Slam for the first time since 2022, have been drawn against Maya Joint and Chan Hao-ching in the women's doubles.