Reigning Wimbledon champion Petra Kvitova advanced to the semi-finals of the WTA New Haven hardcourt tournament on Thursday with a 6-4, 6-1 triumph over Czech compatriot Barbora Zahlavova Strycova.
Fourth-ranked Kvitova next will face Australia's Samantha Stosur, who ousted Belgium's Kirsten Flipkens 6-3, 4-6, 6-3 in the final warm-up event for the US Open, which begins on Monday.
Second seed Kvitova, the 2012 New Haven winner who lost to Simona Halep in last year's final, will be the third seed at the year's last Grand Slam event and will open her Flushing Meadows fortnight next week against France's 73rd-ranked Kristina Mladenovic.
Kvitova, a 24-year-old left-hander, won their first meeting in 2008 at Paris but lost to Mladenovic, 21, last year in Paris.
Slovakia's Magdalena Rybarikova defeated American Alison Riske 7-5, 0-6, 6-4 to book a semi-final berth against Italy's Camila Giorgi, who defeated Spain's Garbine Muguruza 6-4, 6-7 (4/7) 6-2.
Giorgi ousted four-time New Haven champion Caroline Wozniacki, the Danish fourth seed and former world number one, in the second round.