The first Masters 1000 tournament of the WTA season started yesterday, and there has already been a shocking upset in Doha (called the Qatar TotalEnergies Open 2025 or Doha Open).

On Tuesday, Marta Kostyuk handily defeated Coco Gauff in straight sets: 6-2, 7-5. Kostyuk started strong, putting Gauff under pressure with her deep groundstrokes and smart court coverage.

The American, known for her speed and defensive skills, struggled to find her rhythm against Kostyuk’s relentless pace. Kostyuk’s ability to convert break points (5/9) and serve at a high level (66% on first serve and 75% on second serves) ultimately made the difference.

Meanwhile, Gauff double-faulted seven times, going 59% on first serves and 50% on second serves. Gauff was 2/3 on break points. Gauff jumped out a 4-2 lead in the second set, before eventually unraveling against Kostyuk.

This win is a significant milestone for Kostyuk, who has been steadily rising in the rankings and proving herself as a serious contender on the WTA tour. The Ukrainian tennis star is the World No. 21 and continues to take down top-ten players.

Kostyuk has now picked up nine wins against players ranked in the top ten, with this being her first win against a top-ten player in 2025. It is her first win against Gauff after three losses (including two last year).

After the match Kostyuk said, “Coco is an incredible fighter. We always have incredible matches. If you haven’t seen our matches, go on YouTube and watch it.”

Meanwhile, this is one of the worst losses Gauff has had since last Summer’s US Open. She finished 2024 extremely strong and then advanced to the quarterfinals of the 2025 Australian Open last month.

Kostyuk will face the winner of Magda Linette and Magdalena Frech in the Round of 16. If she can win there, Kostyuk is looking at a potential matchup against Paula Badosa or Leylah Fernandez in the quarterfinals.

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