Defending champion Maria Sharapova defeated Anastasia Pavlyuchenkova 6-4, 6-3 on Thursday to set up a Porsche Grand Prix quarterfinal clash with top-seeded Agnieszka Radwanska.
The sixth-seeded Sharapova needed little over an hour-and-a-half to defeat her fellow Russian, keeping alive her bid to win the tournament for the third year-in-a-row.
Polish world no. 3 Radwanska was rarely troubled in wrapping up her 6-3, 6-2 win over Italy's Roberta Vinci in 1 hour 19 minutes.
Fifth-seeded Jelena Jankovic faces Italy's Flavia Pennetta later Thursday for a quarterfinal place against Alisa Kleybanova, who upset the third-seeded Petra Kvitova on Wednesday.
Serbia's ninth-seeded Ana Ivanovic was to play German wild card Julia Goerges, with Germany's highest-seeded Angelique Kerber (4), facing Carla Suarez Navarro of Spain.
Svetlana Kuznetsova of Russia was scheduled to take on second-seeded Simona Halep in Thursday's late match.
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