Kvitova storms into semis

Stuttgart - Wimbledon champion Petra Kvitova beat former French Open winner Francesca Schiavone for the second time in five days on Thursday, 6-2, 6-2 for a quarter-final berth at the Porsche Grand Prix.

The third-seeded Kvitova won five games in a row from 2-1 down in each set and wrapped up the second round match against 11th-ranked Schiavone with a volley winner after 59 minutes of play.

Kvitova also beat Schiavone in the Fed Cup semi-finals on Saturday on Ostrava, on hard-court, as the title-holding Czechs prevailed over top seeds Italy. The 2010 French Open champ Schiavone has struggled this year, with Thursday's defeat her sixth in seven matches.

"I am surprised how well I played my first match on clay," said Kvitova. "I know I can beat a lot of good players with my aggressive game."

The top four seeds in Stuttgart - Victoria Azarenka, Maria Sharapova, Kvitova and Agnieszka Radwanska - had first-round byes at the indoor clay event which is the first major tune-up for the French Open which start in late May.

Sharapova and Radwanska made the quarters in Wednesday, Azarenka was set to play Andrea Petkovic later Thursday, and Stuttgart holder Julia Goerges was up against Samantha Stosur in a repeat of the 2011 semis.