American Robby Ginepri moved easily into the Japan [Images] Open quarter-finals with a 6-4, 6-4 victory over Luxemburg's Gilles Muller on Thursday.

The third seed showed glimpses of the form that took him to the U.S. Open semi-finals last month, wrapping up victory in 70 minutes.

"I thought I returned extremely well, which helped me get into a lot of his service games, and that won the match," said Ginepri, who lost in five sets to Andre Agassi [Images] at the year's last grand slam.

"I don't feel as sharp as I did in the summer but that's going to change shortly."

Ginepri, who lost to British teenager Andy Murray in the quarter-finals in Bangkok last week, will play Germany's [Images] Bjorn Phau in the last eight. Phau thrashed 10th seed Kenneth Carlsen of Denmark 6-1, 6-2.

Second seed Radek Stepanek beat fellow Czech 7-5, 6-4 in a second round match, and American Taylor Dent, seeded fourth, overpowered Russia's [Images] Dmitry Tursunov [Images] 7-3, 7-6.

Top seed Mariano Puerta, who on Wednesday denied a report he had tested positive for a banned substance at this year's French Open, plays Marcos Baghdatis of Cyprus in the evening session.

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