Last week's runner-up in China, Klara Zakopalova, was a second-round upset victim Wednesday at the Hobart International tennis event, a final Australian Open tune-up.

Capable Bulgarian Tsvetana Pironkova ousted the third-seeded Czech Zakopalova 3-6, 6-4, 6-2 on the hardcourts at Hobart International Tennis Centre. Zakopalova lost to Chinese star Li Na in last week's final in Shenzhen.

Also in Hobart on Day 4, qualifier and Aussie crowd favorite Jarmila Gajdosova drilled Belarusian Olga Govortsova 6-3, 6-1, Romanian Monica Niculescu overcame Chinese Peng Shuai 3-6, 6-4, 6-4, and Belgian Kirsten Flipkens subdued Serbian Bojana Jovanovski 6-3, 6-2.

Thursday's quarterfinals will pit eighth-seeded Sloane Stephens against qualifier and fellow American Lauren Davis, ninth-seeded and defending champion Mona Barthel versus Pironkova, Gajdosova against Russian Elena Vesnina, and Niculescu versus Flipkens.

The German Barthel defeated Belgian Yanina Wickmayer in last year's Hobart finale.