PARIS: Iga Swiatek’s 25th birthday celebrations turned sour at the French Open on Sunday as the former champion lost 7-5 6-1 to Ukrainian 15th seed Marta Kostyuk, her bid for a fifth title ending just when she had looked to be rediscovering ‌her rhythm.

There ‌was little to separate ‌the ⁠duo in the ⁠early exchanges as they twice traded breaks, before Kostyuk came up with a tight hold in the 11th game and raised her level at the end ⁠to claim the opening ‌set with ‌a backhand crosscourt winner.

It was the first ‌time that Kostyuk had taken ‌a set off the third-seeded Pole after three straight defeats in their previous meetings, and she sensed a ‌big upset when she went ahead 3-1 in the ⁠next ⁠set after a battling effort.

The Rouen and Madrid champion held her nerve from there to take her record on clay this season to 15-0, and book a meeting with seventh-seeded Ukrainian Elina Svitolina or 11th-seeded Swiss Belinda Bencic in the next round of Roland Garros.