Venus Williams of the U.S. celebrates her victory against Shahar Peer of Israel during the US Open tennis tournament in New York, September 5, 2010. [Xinhua/Reuters Photo]

Venus Williams outclassed Francesca Schiavone in two tough sets to reach the semifinals of the U.S. Open on Tuesday.

The third seed and two time U.S. Open champion battled past French Open champion Schiavone 7-6 (7-5), 6-4, maintaining her momentum for third Flushing Meadows trophy.

Williams, the winner in 2000 and 2001 here, will next play against the winner between defending champion Kim Clijsters of Belgium and Australian fifth seed Sam Stosur.

Neither player could establish any dominance on serve but to break each other two times to prolong the opener into a tiebreak.

Schiavone recovered from 4-1 down in tiebreak and a beautiful drop volley had the sixth seed clenching her fist at 5-5, but two forehand errors handed Williams the set.

The American took control early in the second set but she twice let breaks slip before cracking the Schiavone serve for the third time to close the match in game 10.

Williams had won all seven previous meetings with Schiavone, including two this year, but the Italian posed a greater threat since winning her maiden Grand Slam title in Paris.

"She played a great match," said Williams. "It's not easy to play in these conditions, it's hard to know what decisions to make, but she played excellent."

The 30-year-old Williams owns seven Grand Slam titles, including the 2000 and 2001 U.S. Opens. But she last made the semifinals at Flushing Meadows in 2007, and hasn't played in the title match in eight years.

Williams is the only American singles player left in tournament. Sam Querrey, the last American man player, lost earlier Tuesday.