China's Li Na overcame Shahar Peer of Israel in three sets in the opening round of the US Open on Monday, maintaining her run of good form at this month's Olympics [Images].

- Images from Day 1

Li, who upset Svetlana Kuznetsova [Images] of Russia [Images] and American Venus Williams [Images] at the Beijing [Images] Games, ousted 24th seed Peer 2-6, 6-0 ,6-1.

The 26-year-old Chinese had been frustrated by the way Peer kept getting everything back in the opening set but she told herself: "You just play your game. And I didn't give up."

Li fell short of an Olympic medal but would not dwell on her disappointment.

"The Olympics is over. Now is the US Open," she said.

Li, seeded 36th, will next meet Sara Errani of Italy [Images], a straight sets winner over Jelena Kostanic Tosic of Croatia.

Three other Asian women were unable to advance on the first day of the year's last grand slam.

Yan Zi fell 6-2, 6-4 to Sweden's Sofia Arvidsson and fellow Chinese Zhang Shuai lost to third-seeded Kuznetsova 6-4, 6-2.

FIRST HURDLE

Aiko Nakamura of Japan [Images] also stumbled at the first hurdle, losing to 29th seed Sybille Bammer of Austria 6-4, 6-2.

Japan's Kei Nishikori, however, put a victory on the board by upsetting men's 29th seed Juan Monaco of Argentina 6-2, 6-2, 5-7, 6-2.

"It was a great win, I think, because he's a good player and seeded," said the Nishikori, seeded 126th.

"I didn't think I was going to win, so I'm happy."

Nishikori next meets 100th seed Roko Karanusic of Croatia, who went four sets to defeat American Ryan Sweeting.

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