Kvitova dispatched Anastasia Pavlyuchenkova 2-6, 6-2, 7-5 to create a semifinal meeting with Klara Zakopalova. Wozniacki defeated Sloane Stephens 7-6 (8-6) 6-2 and will meet Simona Halep in the semifinals.
Zakopalova rallied past Elena Vesnina in the quarterfinals 4-6, 6-0, 6-4 and Halep won over Ekaterina Makarova 6-1, 7-6 (8-6).
Kvitova is looking for her second championship of the year and the 11th of her career. Wozniacki has 20 tournament victories to her credit, but none have come this season.