Sydney, Australia (SportsNetwork.com) - Petra Kvitova and Angelique Kerber were quarterfinal winners Wednesday at the Sydney International tennis event, a final hardcourt Australian Open tune-up.

The second-seeded Wimbledon champion Kvitova rallied past Aussie favorite Jarmila Gajdosova 4-6, 6-3, 6-4.

Gajdosova knocked out Andrea Petkovic and 2014 Aussie Open runner-up Dominika Cibulkova to reach the quarterfinals.

Next up for Kvitova is defending Sydney champion Tsvetana Pironkova, who handled Czech Barbora Zahlavova Strycova 6-4, 6-1. Pironkova upset Kerber in last year's final here.

Kerber, the No. 5 seed, came back from a set down to beat Spaniard Garbine Muguruza 0-6, 6-1, 6-4. Kerber will meet rising Czech Karolina Pliskova in the semifinals.

Pliskova outlasted Spain's Carla Suarez Navarro 4-6, 6-4, 6-0.

This week's winner will take home $124,000.