Gauff steadies serve to beat Sonmez in US Open opener

What happened: Coco Gauff began her US Open campaign with a 6-3, 6-4 victory over Turkey's Zeynep Sonmez on Tuesday night at Arthur Ashe Stadium. The WTA reported that the fourth-seeded American completed the first-round match in one hour and 20 minutes, holding to love in the final game after also opening the contest with a love hold.

Watch the highlights:

Gauff's serve provided the clearest measure of her performance. Official WTA match statistics credited her with five aces and three double faults. She landed 41 of 66 first serves, won 29 of those 41 points and saved four of the five break points she faced. BBC Sport reported that she won 93% of her first-serve points during the opening set.

The second set supplied the match's main pressure point. Sonmez recovered an early break to level at 2-2, then held three break points as she tried to move ahead. According to the WTA, Gauff survived a nine-minute game featuring six deuces to hold for 3-3. She broke in the next game and maintained that advantage to finish the match in straight sets.

BBC Sport reported that Gauff's improved delivery follows sustained technical work with biomechanics specialist Gavin MacMillan, whom she hired before last year's US Open. The adjustments have focused on a more consistent ball toss and wrist position. Her double-fault total remains high across the season, but the BBC said her average per match has fallen and her accuracy improved during her recent Cincinnati title run.

Why it matters: The home favorite arrived in New York after winning the Cincinnati Open earlier in August and carried that form through a potentially difficult opening match. The WTA said Gauff has now won seven of her eight US Open first-round matches. She also reached 81 Grand Slam match victories since the start of 2020, trailing only Iga Swiatek and Aryna Sabalenka in that span.

Gauff is seeking another title at the tournament where she won her first Grand Slam singles championship in 2023. BBC Sport reported that she will face either Spain's Paula Badosa or Australia's Daria Kasatkina in the second round. Her next match will offer another examination of a serve that looked dependable against Sonmez, although one successful round does not settle how it will hold up deeper in the draw.