NEW YORK -- Venus Williams hit bottom, so to speak, when she double-faulted three times in one game, whiffed at an overhead, stomped to her chair, missed the seat and plopped to the court.

The sheer indignity of it all only compounded the frustration she felt throughout her match Tuesday against a relentlessly net-charging Nathalie Tauziat.

	Venus Williams found herself stretched to the limit early Tuesday before eliminating Nathalie Tauziat.

Yet even on her worst day, Williams still was good enough to win, 6-4, 1-6, 6-1, and extend her tour-leading streak to 24 matches as she moved into the semifinals of the U.S. Open.

Williams, seeded No. 3, will have to play far better to beat No. 1 Martina Hingis on Thursday.

Hingis knocked out Williams in the semis last year before losing to Serena Williams in the title match, and has been the most dominant woman in the tournament so far this year. She reached the semis Tuesday night with a 6-0, 7-5 rout of No. 6 Monica Seles, and has yielded only 15 games in five matches without dropping a set.

Williams had not lost a set in the tournament, and had dropped only three sets in her winning streak. But after a listless first set against Tauziat, and a sleepwalking second set filled with unforced errors, she powered up her serve and groundstrokes a notch to wear down the small but spirited Frenchwoman.

"You walk off against her and you don't have the impression you played a tennis match," Tauziat said. "You feel as if you've been in a tag-team wrestling match or a boxing bout, but not tennis. She just bangs away. It's in, it's out, it's a double-fault, it's an ace. You just never know what's coming."

Half the time, Williams also didn't know what was coming off her racket as she sprayed her serves in sundry directions and whacked groundstrokes wildly. She had seven aces and 10 double-faults. She was too aggressive or too tame, sometimes reaching for balls that would have flown long, or hitting shots safely down the middle.

"A lot of times I was rushing when I really could have just taken my time and hit some nice passing shots or some lobs," she said. "I never get upset when I'm playing, but today ... it was very strange.

"I thought I had quit playing tennis like that. It's been a little while since I played a match like that. I can't accept these things."

She had not played so badly in any other match during her winning streak from Wimbledon to the U.S. Open, she said, and had not played a worse set during that stretch than the second one against Tauziat.

Williams didn't blame her problems on the gusting wind or the fatigue of playing day and night for the past four days because of the rain delays and her singles and doubles schedule with her sister, Serena. Rather, she chalked it up to just one of those days best forgotten.

Her frustration was epitomized by her misadventure with her chair after she was broken on serve in the third set. She had taken control of the set by sweeping the first four games but then came unglued again, double-faulting three times, completely missing the ball on an overhead swing, and netting a backhand at break point.

Pouting and stomping her feet, she marched to the sideline on the changeover, missed the seat as badly as she had missed the overhead, and fell awkwardly. Tauziat and spectators laughed, but Williams didn't see any humor in it.

"I was just angry," she said. "I just couldn't see."

But when that moment of blind rage passed, Williams recovered her poise enough to break the tiring Tauziat one more time and close out the match with only two unforced errors in the last two games.

"Finally, physical ability was the decisive factor," Tauziat said, "because right at the end I hit volleys that nobody else would have got to, and Venus was there all the time."

But Tauziat also thought she had exposed Williams' vulnerability a bit.

"I think if she (is to) win the tournament, she needs to improve her level," she said. "I don't think she is going to win if she plays like this."