PARIS, France (AFP) — Four-time French Open champion Iga Swiatek exited Roland Garros on Sunday as the top seeds continued to fall at the start of the second week, while Alexander Zverev booked his spot in the quarterfinals.

The Polish third seed endured a miserable 25th birthday as she went down 7-5, 6-1 to Madrid Open winner Marta Kostyuk.

Since winning Roland Garros in her second appearance at the tournament in 2020, Swiatek had never gone more than two years without hoisting aloft the Coupe Suzanne Lenglen, but after Aryna Sabalenka ended her bid to win a fourth consecutive French Open in the semi-finals last year, she has lost her unbeatable status on clay.

Indeed since last winning in Paris in 2024, Swiatek has only lifted three titles in the two subsequent seasons.

"It is harder a bit to handle stress for me in, like, (the) last year," she said.

"So I feel like today I felt off, you know, and I did mistakes that I didn't want to do, and I wanted to play safe, but the ball flew everywhere.”

"Suddenly these feelings came back, and I tried to work on it with my dialogue inside, but it was tough today. Yeah, so it all kind of went drastically down, and I played worse and worse."

After breaking Kostyuk in the first set to edge 4-3 ahead, Swiatek's serve totally deserted her and she failed to hold again as the Ukrainian hit back to claim the opener and then raced through the second frame.

For Kostyuk, reaching a first quarter-final at Roland Garros was just the latest high mark in a fine clay-court season, in which she claimed the 250-level event in Rouen, as well as a first WTA 1000 title in the Spanish capital.

Elina Svitolina next stands between her compatriot and the last four after she fought back to beat Swiss 11th seed Belinda Bencic 4-6, 6-4, 6-0.

After winning a first WTA 1000 title in eight years earlier in May at the Italian Open, Svitolina's last-eight encounter with Kostyuk will pit against each other the two winners of the main warm-up events to Roland Garros.

"It's exciting. Definitely she's been playing really well," Svitolina said of Kostyuk, who is on a 15-match win streak on the red dirt.

"I feel like it's going to be an exciting battle for Ukraine, as well, you know, that there will be one Ukrainian in the semis."

Sorana Cirstea continued her remarkable renaissance during her farewell season on tour as the 36-year-old bested Chinese world No. 148 Wang Xiyu 6-3, 7-6 (7/4).

The Romanian will face Russian eighth seed Mirra Andreeva in what will be her first quarter-final appearance at the French Open in 17 years.

Teenager Andreeva, who defeated 170th-ranked Swiss Jil Teichmann in straight sets, will be targeting a second semi-final in three years at Roland Garros.

Rising Spanish star Rafael Jodar has been no stranger to lengthy matches in his debut Roland Garros campaign but the 19-year-old's five-set win over fellow countryman Pablo Carreno Busta was even longer drawn out than it would otherwise have been as the heatwave that defined the first week subsided to rain, which caused brief delays in play.

Jodar battled back from two sets down to beat the 34-year-old 4-6, 4-6, 6-1, 6-2, 6-2.