Gauff has not appeared confident with her serve since beating Aryna Sabalenka on clay earlier this summer. She won three matches in the US Open tuneup earlier at the Cincinnati Open, but lost to Italy's Jasmine Paolini in the fourth round.

American tennis player Coco Gauff has parted ways with one of her coaches Matt Daly and brought on biomechanics expert Gavin MacMillan.

Coco Gauff made a surprising coaching change just days before the 2025 U.S. Open. The top-ranked American woman player parted ways with her coach Matt Daly on Wednesday, The Athletic 's Matthew Futterman reported. Gauff hired Daly after last year's U.S. Open to specifically work on her serve and her forehand.