Coco Gauff begins her U.S. Open title defense Tuesday night against Zeynep Sonmez, and the favorite’s burden is not the question. The market expects Gauff to win, but the better betting line points to Sonmez keeping the match close enough to cover +6.5 games at +110 through FanDuel.
That sets up a familiar kind of U.S. Open opener: one player arrives with a trophy pedigree and recent results, while the other arrives with enough form to make the number matter. Gauff won the 2023 U.S. Open, reached the semifinals at Wimbledon this year and also made the semifinals at the National Bank Open in Canada before winning the Cincinnati Open in her most recent tournament. She beat Marie Bouzkova, Marta Kostyuk and Jessica Pegula to take that title, and she enters New York with the weight that comes from being the defending champion.
Sonmez, 24, is not being asked to win the match outright. She is being asked to survive long enough for the spread to cash, and her season gives that case some support. She has eight wins against women ranked in the top 50 this season, including victories over Ekaterina Alexandrova and Jasmine Paolini. She also reached the third round at both the 2025 Wimbledon and this year’s Australian Open, and her best U.S. Open finish was a second-round appearance last year.
That is why this matchup is being framed around games rather than an upset. Gauff is the clear pick to advance, and she has already shown she can handle the biggest stages, but Sonmez has enough recent results against stronger opposition to make a wide margin less certain. The two have never met at the professional level, which adds another layer to a first-round match that is more about whether Gauff can start fast than whether she can be pushed.
Gauff’s path to a second U.S. Open title starts with the kind of opening round that can either announce another deep run or expose a little rust. Sonmez does not need a breakthrough to matter here; she only needs to stay within the number long enough to turn the favorite’s return to New York into a closer contest than the odds suggest.
