Top-seeded Iga Swiatek got off to a slow start but rallied for a 3-6, 6-1, 6-1 victory over China's Qinwen Zheng on Thursday in the third round of the Western & Southern Open in Mason, Ohio.
The Polish star moves on to a quarterfinal matchup in the Cincinnati-area event against 10th-seeded Marketa Vondrousova of the Czech Republic. Vondrousova, the reigning Wimbledon champion, beat the United States' Sloane Stephens 7-5, 6-3 on Thursday.
Swiatek lost her serve three times in the first set against Zheng but was broken just once the rest of the way.
"I always feel like I just need to focus on myself and what I want to do on court," Swiatek said. "The tactics obviously is important, but it's the second-most important thing because the best thing I can do is just kind of play my game and focus on adjusting my game so I can play the best in these conditions. That's what I'm gonna do."
Zheng fell to 0-4 in her career against Swiatek due in large part to poor serving — she had seven double faults and just four aces, and she put only 36 percent of her first serves in play.
Vondrousova took advantage of four of her five break-point opportunities while saving three of the four break points on her serve. The match was contested in breezy conditions.
"When we were warming up it wasn't that windy, but when we came on the court I as like, 'Oh my god, what is happening?'" Vondrousova said. "You didn't know what was going to happen. I thought we were serving good in the wind, but it was very tough to play some rallies."
Swiatek and Vondrousova have faced off just once previously, a 6-1, 6-2 win for Swiatek at the 2020 French Open.
Elsewhere on Thursday, second-seeded Aryna Sabalenka of Belarus advanced to the quarterfinals while third-seeded Jessica Pegula of the United States and fourth-seeded Elena Rybakina of Kazakhstan were both eliminated.
Sabalenka got past 14th-seeded Russian Daria Kasatkina 6-3, 6-3, and the Czech Republic's Marie Bouzkova crushed Pegula 6-4, 6-0.
Italian qualifier Jasmine Paolini made it to the quarterfinals of a WTA 1000 event for the first time when Rybakina retired due to an undisclosed injury while leading 6-4, 2-5.
Fifth-seeded Ons Jabeur of Tunisia led 5-2 when Croatia's Donna Vekic retired because of a viral illness. The Czech Republic's Karolina Muchova ousted eighth-seeded Maria Sakkari of Greece 6-3, 2-6, 6-3, and seventh-seeded Coco Gauff of the United States blitzed the Czech Republic's Linda Noskova 6-4, 6-0.
—Field Level Media