Venus Williams hitting a backhand against Francesca Schiavone in the...

Venus Williams hitting a backhand against Francesca Schiavone in the second set of their quarterfinals match at the 2010 United States Open. (Sept. 7, 2010) Credit: Newsday/J. Conrad Williams Jr.

Kim Clijsters, the Open's defending champion, ran up against a player making championship strides last night.

After three highly entertaining sets, Clijsters is through to the semifinals, where she will meet Venus Williams. But first she had to meet the challenge of Samantha Stosur, the French Open finalist and a player decidedly on the rise. Clijsters won, 6-4, 5-7, 6-3, surviving some serving hiccups and Stosur's big serve and forehand.

Stosur broke Clijsters' serve seven times, but crucially, Clijsters broke Stosur eight times. The third set began bizarrely with six consecutive breaks of serve. It appeared that whoever held serve would win, and Clijsters held in the seventh game, broke Stosur again and won the ninth and final game with an ace for the match. It was Clijsters' 19th straight win in the U.S. Open.

"I was seeing the ball well when she was serving," Clijsters said. "If I could get the ball on her backhand, I felt I was in control of the points. After that final break I said, 'OK, just one point at a time.' "

Williams defeated a pesky Francesca Schiavone in her quarterfinal match. The scores were 7-6 (5), 6-4, and the match was as close as the score line indicated.

Schiavone's chief weapon was her backhand, and when she could maneuver to strike it, it kept Williams on the baseline. Schiavone is the only player in the top 20 other than the injured Justine Henin to hit the backhand one-handed. Williams brought her big serve, her hard forehand and her significant range.

The first set was a microcosm of the match, with Williams earning a break of Schiavone's serve after five deuces. Then Schiavone earned a break of Williams' serve in the second game. Schiavone double faulted to give Williams the fifth game, then Williams double faulted to give the break back in the eighth game. The players stayed on serve to force the tiebreak.

Williams jumped out to a 4-0 lead in the tiebreak, only to see Schiavone win the next four points to equalize. This was going to be a tussle. But at 5-5, Schiavone hit two forehands long and Williams took the first set.

Schiavone gave up a break in the fourth game of the second set and was playing from behind from there. The match ended with four straight breaks of serve, the last one Schiavone's. It was Williams' eighth straight career win over Schiavone.

"I feel like when the stakes were higher, I was able to raise my game," Williams said. "She did, too. She played some great points. She's just so feisty that you have to kind of keep her at bay."

The Open champion in 2000 and 2001, Williams has reached the semifinals here only twice since winning the titles. Williams lost to Clijsters in the round of 16 last year, when Clijsters returned after a two-year absence to heal from injury and have a baby.

"I'm sure that match made a big difference for her, because she went on to win the title," Williams said. "I'm sure we'll have another good matchup. I'd like to kind of flip the way it turns out."

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