Coco Gauff Beats Zeynep Sonmez as Reworked Serve Powers US Open Start

Coco Gauff opened her US Open campaign with a 6-3, 6-4 first-round victory over Turkey’s Zeynep Sonmez on Tuesday, using a more dependable serve to take control in New York. BBC Sport reported that the 22-year-old American began with a hold to love and relied on the same shot to navigate pressure later in the match.

Watch the highlights: https://www.youtube.com/watch?v=hQxEAcgPitg

Gauff, the fourth seed at Flushing Meadows, established the pattern immediately. Her opening service game included a 112mph ace down the middle, an unreturned first serve and another ace, allowing her to hold in less than 90 seconds. She won 93 percent of the points behind her first serve during the opening set as Sonmez struggled to put returns into play.

The second set presented a sterner examination. Gauff broke for a 1-0 lead, but Sonmez responded to level at 2-2 and later earned three break points that could have put her ahead 4-2. Gauff escaped with an ace placed wide and a 115mph first serve that Sonmez could not return, then broke in the next game to move in front 4-3.

Serving for the match, Gauff struck three more unreturned first serves, each recorded at just below 120mph, to create three match points. Sonmez lost the first of them after a short rally, completing Gauff’s straight-sets win and sending the two-time major champion into the second round, where she was due to face either Spain’s Paula Badosa or Australia’s Daria Kasatkina.

The performance followed a year of technical work with biomechanics specialist Gavin MacMillan. Gauff added MacMillan to her coaching team shortly before the 2025 US Open after a high number of double faults at the Cincinnati Open. BBC Sport reported that their work has focused on a more consistent ball toss, keeping the toss from drifting too far forward and holding her wrist in a straighter position.

Double faults have not disappeared entirely: Gauff has recorded 301 on the WTA Tour this season, more than any other player, though the BBC noted her average of 5.6 per match is lower than that of many peers. The broader improvement was also evident during her run to the Cincinnati Open title earlier in August. Against Sonmez, increased accuracy without sacrificing speed gave Gauff a reliable way out of difficult service games and a winning start at the tournament where she captured her first Grand Slam singles title in 2023.