Coco Gauff opened her 2026 US Open campaign with a straight-sets victory over Zeynep Sonmez, winning 6-3, 6-4 on Tuesday in New York. The result moves the fourth seed into the second round and continues a strong late-summer run.

The match lasted about 1 hour 20 minutes. Gauff produced the moment of the contest in a marathon six-deuce, nine-minute game in which she saved three break points before holding. That sequence proved pivotal to the outcome as Sonmez was unable to recover the momentum.

Tournament coverage highlighted Gauff's serve as noticeably improved and a rejuvenated weapon in the victory. Observers credited the stronger serving performance as a key factor that helped her close out the match in two sets.

Gauff has made technical changes aimed at curing previous serving problems, working with biomechanics expert Gavin MacMillan to refine her toss and technique and to address past serving 'yips.' Coverage linking that work to her renewed serve noted the changes were implemented after the issues that emerged in 2025.

Her arrival at Flushing Meadows followed a title in Cincinnati earlier in August 2026, a run of form that observers placed alongside the adjustments to her serve.

Seeded fourth at the tournament (world No. 4), Gauff will face either Paula Badosa or Daria Kasatkina in the second round.

Contemporary reporting tied Gauff's 2025 serving struggles — including visible, emotional practice sessions described as her 'practising in the rain' — to the technical overhaul that preceded this year's US Open, framing the opening-round win as a sign of recovery from that period.