NEW YORK -- Pressed by a player who started the year ranked No. 99 in the world, Venus Williams survived an early scare Friday night and stayed on course in the U.S. Open.

Williams, seeded No. 3 in America's Grand Slam, was broken four times in the first set by Meghann Shaughnessy and forced to a tiebreaker before winning her third-round match 7-6 (7-3), 6-1.

	Martina Hingis has lost just seven games in her three U.S. Open singles victories this year.

The victory kept Williams on track for what many anticipate would be a semifinal showdown with No. 1 seed Martina Hingis, who had far less trouble advancing Friday.

"I don't see this as a wakeup call," said Williams, who had eight double faults and 27 unforced errors. "I felt a little tight because I was thinking, `What am I going to do to turn this around?"'

Eventually, she did and felt good about the effort.

"By the time I got to the second set, I felt it was pretty much at an end," Williams said. "As far as confidence, in the big points, the big situations, I'm at an advantage," she said. "I'm not backing down or making mistakes. I might have in the past."

Friday night's victory over the unheralded right-hander from Scottsdale, Ariz., put Williams into the round of 16, where she will face unseeded Magui Serna of Spain. Serna upset 13th-seeded Amanda Coetzer 7-5, 7-6 (7-3).

In the time it takes some weekend hackers to stretch and warm up, Hingis zipped through the fastest match of the U.S. Open and gave warning to the Williams sisters that she's ready to take them on.

Hingis hasn't won a major title since the 1999 Australian Open, but she's off to her best start in Grand Slam play since then with three straight-sets victories in which she's yielded a total of only seven games.

"It will be great, definitely, to win a Grand Slam right here. This is my chance," the top-seeded Hingis said after reaching the fourth round with a 37-minute 6-1, 6-0 romp past Tathiana Garbin of Italy.

"I was taking her very seriously today, even though I won the last time so easily," said Hingis, who beat Garbin by the same score in the same round at the French Open in May. "I knew she was injured there a little bit. She had so far pretty easy wins here in the first couple rounds. I had to play well. That's what I did."

Hingis' 45-minute warmup with a practice partner took longer and was more intense than the match. But it's all part of her preparation for an expected clash with Venus Williams in the semifinals, with the winner perhaps playing defending champion Serena Williams in the final.

Venus nearly got derailed by Shaughnessy, who won the first three games of the match and had Williams struggling. In the end, however, the older of the Williams sisters prevailed for her 22nd consecutive match victory of the year, longest on the WTA Tour this season.

"She was playing very well, living off my power," Williams said of Shaughnessy. "I was little confused on my serve in the first set. I never felt I would lose the set.

"In the end, the win is in my record."

"I watch her when she plays," Hingis said of Venus Williams, who beat her in the Wimbledon quarterfinals en route to the title in July. "I know quite well what her game is. She maybe improved in some of the parts of her game. I just have to play mine, not get too intimidated, do whatever I've been doing so far."

Hingis said she watched on television when Venus beat Anne-Gaelle Sidot in the first round. And she was probably tuned in for Friday night's match against Shaughnessy, the niece of Boston Globe baseball columnist Dan Shaughnessy.

It didn't take long for Williams to realize she had a tough opponent in Shaughnessy. Just three games, actually -- all won by Shaughnessy.

"I know that, playing well, I can stay with players like her," Shaughnessy said. "It's just a matter of really believing that I can win and that I will win."

Once Williams began winning games, the 21-year-old Shaughnessy, ranked 48th in the world, ran her lead to 5-3 and served for the set.

But Williams began to find the court with her groundstrokes and won three straight games to take a 6-5 lead. When Shaughnessy held to force the tiebreaker, Williams kept her opponent's hopes alive with consecutive double faults.

Hope faded fast after that.

Meanwhile, Hingis was thinking about the Williams.

"Both Serena and Venus, they have a little bit of concentration weaknesses in their game," Hingis said. "(Venus) said herself when she gets into the big matches she tends to be better."

Hingis' next match against No. 11 Sandrine Testud, who sped through a 6-0, 6-1 victory over Kristie Boogert, may take longer. But the outcome is not likely to surprise anyone. Hingis has won all 11 of their match, including five this year.

Sixth-seeded Monica Seles squeaked through with a 6-3, 4-6, 6-4 victory over Chanda Rubin. Next up for Seles is No. 15 Jennifer Capriati, a 6-2, 6-3 victor over Adriana Gersi.

Seles and Capriati have met twice at the U.S. Open, the first time in a brilliant 1991 semifinals when Seles won in a third-set tiebreaker, and again last year when Seles won in straight sets.

"Obviously, I'm not going to go in there think that it's supposed to be like an epic match or anything," Capriati said. "I'm not really thinking about in the past or whatever between us.

"I'm kind of happy I haven't been put to the limit because I need to really save as much energy as possible to play Monica. I'm kind of glad I didn't have really tough matches."

In other early matches, No. 8 Nathalie Tauziat downed Janet Lee 6-3, 6-2; and No. 9 Arantxa Sanchez-Vicario bested Allison Bradshaw 7-6 (7-2), 6-0.