Gauff battles on to master new serve, Sinner and Osaka also in action

The U.S. Open's third round continues on Saturday with world number three Coco Gauff hoping that her misfiring serve does not cause her further headaches, while Jannik Sinner and Naomi Osaka will be aiming to continue their run of straight-set wins.

TOP WOMEN'S MATCH: MAGDALENA FRECH V COCO GAUFF

Coco Gauff's mental battle to master her new serve continued in the second round against Donna Vekic as the American was reduced to tears after failing to hold her serve due to a flurry of errors.

The 2023 champion, who produced seven double faults in the first set but only one in the second, rallied to secure victory and progress to the third round.

She said she was not embarrassed about showing her vulnerable side.

"It feels human. Being an athlete, people kind of disregard that side of us, the human side of things," she told reporters.

"When I'm out there in that moment, I kind of give into the pressures, but I feel like that's normal. I feel like every pro athlete who's been on the pedestal that I've been on has felt that pressure at some point in their career where they showed it publicly like I did or privately."

Gauff said it has been difficult to get used to her new serving technique after biomechanics specialist Gavin MacMillan joined her camp just days before the U.S. Open.

"I think my body has been used to doing it one way for how long, or however long, and I think for me it's just counteracting that in those moments and trying to stay in the right motion that we've been working on," she said.

"Yeah, it's been tough doing it all over and kind of refactoring everything, a motion that I knew very well. But I know for the future this is the right step forward."

Gauff had little trouble beating Magdalena Frech in both of their