CINCINNATI: Iga Swiatek used an outfit change to help her reset after a poor start and beat China’s Zheng Qinwen 3-6 6-1 6-1 on Thursday and set up a Cincinnati Open quarter-final clash with Wimbledon champion Marketa Vondrousova. Second seed Aryna Sabalenka sailed into the last eight with a tidy 6-3 6-3 win over Russia’s Daria Kasatkina but it was the end of the line for world number three Jessica Pegula and number four Elena Rybakina. Pegula, champion in Canada last week and winner of a Tour best 27 hardcourt matches this season, was dumped out 6-4 6-0 in a rain disrupted contest by Czech Marie Bouzkova, who improved to 4-2 against the American. Last year’s Wimbledon champion Rybakina had looked poised for smooth passage, taking the opening set against Italian qualifier Jasmine Paolini 6-4, but retired trailing 2-5 in the second with an unspecified injury. Awaiting Swiatek in the next round will be Vondrousova, who converted four of five break points during a 7-5 6-3 victory over Sloane Stephens. Tunisian fifth seed Ons Jabeur also benefited from a retirement when Croatia’s Donna Vekic quit while trailing 5-2 in the opening set. In a battle of the teenagers, 19-year-old Coco Gauff claimed a 6-4 6-0 win over 18-year-old Czech Linda Noskova, who failed to hold serve the entire match. Karolina Muchova surprised eighth seed Maria Sakkari 6-3 2-6 6-3 to set up an all Czech showdown against Bouzkova.