STUTTGART: Defending champion Maria Sharapova defeated Anastasia Pavlyuchenkova 6-4, 6-3 on Thursday to set up a quarter-final clash with top-seeded Agnieszka Radwanska at the Porsche Grand Prix.

Sharapova needed little over an hour-and-a-half to defeat her fellow Russian and it was in stark contrast to her struggles of the previous day when she needed three tie-breaks and almost three-and-a-half hours to defeat Lucie Safarova of the Czech Republic in a first round tie.

Seeded sixth this year, Sharapova is aiming for a third straight title on the red clay of Stuttgart as the preparations for the French Open get fully underway.

The four-time Grand Slam champion looked solid enough on serve, with just five double-faults to eight by her opponent and she had Pavlychenkova under constant pressure with her booming returns.

Polish world no 3 Radwanska was rarely troubled in wrapping up her 6-3, 6-2 win over Italy’s doubles specialist Roberta Vinci in an hour and 19 minutes.

Fifth-seeded Jelena Jankovic advanced to a quarter-final against Russia’s Alisa Kleybanova, who upset the third-seeded Petra Kvitova on Wednesday.

Serbia’s Jankovic came from a set down to beat Italy’s Flavia Pennetta 3-6, 6-2, 6-3 in their second round match on Thursday. Pennetta had fired 10 aces to none in her 7-5, 3-6, 6-1 win over wild card Andrea Petkovic in her first-round match on Wednesday.

Also on Wednesday, Kleybanova defeated Kvitova 6-2, 7-6 (7-3) to provide the first major upset at the event.

The 102nd-ranked Kleybanova rallied from 5-3 down in the second set to beat her Czech opponent for her first victory against a top-10 player since winning her battle against Hodgkin’s lymphoma, which kept her out between May 2011 and March 2012.—Agencies