Stosur marches on in Dubai

The US Open champion is slowly returning to her best despite being brushed aside by Victoria Azarenka in the final of the Qatar Open last week.

And she was delighted to move past the in-form Czech, who took the match into a decider when sneaking the second set tie-breaker 7-5.

"I don't think I did much wrong in the second set and thought I played a good match," said Stosur. "I held serve and in the third set I took my opportunities to break."

Jelena Jankovic awaits in the last eight after the Serb eased past Flavia Pennetta of Italy 6-4 6-2.

Still playing with a tear in her bandaged left thigh, Jankovic recovered well from an early 1-3 deficit, adopting a more positive approach and finding a good combination of aggression with consistency.

Fifth seed Agnieszka Radwanska also progressed, defeating Israeli Shahar Peer 7-5 6-4 on an outside court to provide Peer with added security.

Wimbledon semi-finalist Sabine Lisicki awaits in the quarter-finals after ninth seed from Germany defeated Iveta Benesova of the Czech Republic 6-3 6-3.

Ana Ivanovic of Serbia defeated Russia's Maria Kirilenko 6-2 7-6.

This week's field has been severely weakened by the late withdrawal of Azarenka through injury, joining Vera Zvonareva, Petra Kvitova and Li Na on the sidelines.

And Julia Goerges of Germany was the beneficiary of Azarenka's absence by brushing aside her replacement, lucky loser Casey Dellaqua, 6-0 6-2.