Top-four seeds reach Prague QFs

The top-seeded Zvonareva was scheduled to meet wild card Magdalena Rybarikova in a second-round bout on Thursday, but the Slovakian withdrew, citing a lower back injury, giving the Russian a walkover into the round of eight.

The second-seeded Peer, meanwhile, handled Bulgarian Tsvetana Pironkova 7-5, 6-2 on the red clay at this French Open tune-up. The Israeli star will meet seventh-seeded Czech crowd favorite Klara Zakopalova in the quarters. Zakopalova outlasted Russian Vera Dushevina 6-4, 1-6, 6-3 on Day 4.

In other second-round action, third-seeded Victoria Azarenka pasted fellow Belarusian Tatiana Poutchek 6-2, 6-2, fourth-seeded Slovenian Katarina Srebotnik subdued Hungarian qualifier Melinda Czink 6-0, 6-2, and Czech Iveta Benesova topped Uzbekistan's Akgul Amanmuradova 6-2, 4-6, 6-3.

Friday's other quarters will pit Azarenka against 16-year-old Czech Karolina Pliskova and Srebotnik versus Benesova, who was a finalist in Portugal just two weeks ago.

The 2008 Prague winner will collect $22,900.