Coco Gauff’s U.S. Open title defense begins with the kind of first-round assignment that can look straightforward until it suddenly is not. On Tuesday night, the 2023 champion opens against Zeynep Sonmez, and the matchup carries the usual early-round tension: one player trying to protect a title, the other trying to turn a strong season into a breakthrough week.
Gauff arrives in New York off a Cincinnati Open title, which is exactly the sort of recent form that makes her look like a legitimate contender again. She won the U.S. Open in 2023 for her first career Grand Slam title, then reached the fourth round in both 2024 and 2025. That is not a defending-champion profile in name only; it is the resume of a player who has repeatedly found a baseline at this event, even when the draw has opened different paths in different years.
Sonmez, though, is not walking into Arthur Ashe Stadium as a mere placeholder. She reached the third round at Wimbledon in 2025, added a second-round run at the U.S. Open later that year, and this year made the third round at the Australian Open. She has also beaten eight women ranked in the top 50 this season, including Ekaterina Alexandrova and Jasmine Paolini. That matters because it suggests her rise is not built on a single hot streak; it is showing up against quality opposition over time.
Why the betting angle matters
The market reflects that gap, with Gauff listed at +110 and the game spread sitting at +6.5 Games. In other words, the expectation is not just that Gauff should win, but that she should do so with enough control to separate from an opponent who has already proven she can trouble higher-ranked players. That is the right starting point for a betting read: Gauff brings the bigger ceiling and the stronger U.S. Open track record, while Sonmez brings enough recent evidence to keep the opener from becoming a formality.
What makes this interesting is that Gauff does not need this match to prove she belongs in the conversation. She already won the event once, and her Cincinnati title only strengthens the sense that she is arriving with momentum. The question is whether she can turn that into the kind of efficient opening that sets up a deep run, rather than a messy early test that leaves unnecessary stress on the draw.
That is where Sonmez becomes more than a footnote. Players who have already reached the third round at Wimbledon and the Australian Open tend to carry a little more belief into these moments, especially after beating names like Alexandrova and Paolini this season. She has a path to make this uncomfortable if Gauff is slow to settle or if the match tilts into longer exchanges than expected.
Still, the broader case leans toward the champion. Gauff has the more proven U.S. Open profile, the better recent trophy form, and the kind of tournament history that usually matters when the pressure rises. For a player trying to add a second U.S. Open title, the opening round is not the whole story — but it is often where the story gets its shape.
For another example of a first-day Grand Slam storyline, the Monday headline on the Athens Open Day One page highlighted Qinwen Zheng as Maria Sakkari returned home, which is a reminder that tournament narratives often start before the biggest names even reach center court. Gauff’s path starts here, and the opener may tell us whether her title defense looks sharp from the outset or merely survives long enough to grow into something more.
