Those who couldn't see the words crawling across the huge monitors on the grounds could hear them on the public address system: "The seating in the Louis Armstrong Stadium is filled to capacity. We invite you to view matches in the grandstand and the field courts."

Problem was, there was nothing on the grandstand, field courts or even the Arthur Ashe Stadium court today that could come close in entertainment value or drama to the match Serena Williams and Belgium's Kim Clijsters played in packed Louis Armstrong. Down a service break in the third set and on the verge of elimination, Williams boldly blasted her way to winning 14 straight points and took a 4-6, 6-2, 7-5 third-round victory in the U.S. Open.

Williams was trailing 5-3 in the third set, with Clijsters, 16, serving for the match and what would have been the biggest upset on the women's side of the draw. No. 7 seed Williams, disgusted with herself for serving poorly and making errors, said later: "I just said at that point, `I'm going to play the way I've been taught to play.' "

Williams broke Clijsters at love, then rocked two aces and a service winner to even the set. Four more points, including a double fault by Clijsters, gave Williams another break and a 6-5 lead.

She closed out the match to advance to a meeting against 16th-seeded Conchita Martinez. The match lasted 1 hour 55 minutes and was punctuated by a week's worth of fist-pumping, athletic shot-making, bad serving, and screaming groundstrokes hit deep into the corners and off both sidelines.

Jennifer Capriati, a relative afterthought at age 23, unseeded and trying to play her way back to where she was eight years ago, defeated 11th-seeded Nathalie Tauziat of France in three sets. Eight years ago, Capriati lost one of the great matches in U.S. Open history to Monica Seles, her fourth-round opponent Monday. The two-time champion and fourth seed defeated Ai Sugiyama, 6-2, 6-3, tonight.

The other high seeds advanced without much drama. Second-seeded Andre Agassi dropped the second set but was always in control of the match and defeated Justin Gimelstob, 6-1, 4-6, 6-3, 6-4. Third-seeded Yevgeny Kafelnikov of Russia had no trouble in a straight-sets victory over Swede Jonas Bjorkman. Defending champion Lindsay Davenport, the second seed, needed only 46 minutes to whip Amy Frazier, 6-1, 6-1.

France's Mary Pierce, the No. 5 seed, defeated Angeles Montolio of Spain in straight sets. Martinez, the 16th seed, beat Russia's Elena Dementieva in three sets. And on the men's side, 15th-seeded Nicolas Kiefer of Germany was eliminated by France's Arnaud Clement in four sets.

But nothing got the Tennis Center buzzing more than the Williams-Clijsters match, which literally had fans running to the entrance gates to secure seats. Williams certainly has played better. She had more double faults (seven) than aces (six) and got in only 44 percent of her first serves.

"I didn't think I made any first serves," she said.

Williams also committed 46 unforced errors, which might have been disastrous except that Clijsters committed 56 and had nine double-faults and no aces.

With both women smacking shots at the baselines and sidelines, the action was entertaining, though hardly a technical success.

"I was making too many errors," Williams said. "And she was making lots of shots. . . . I'm going to go practice today. It was really ridiculous the way I was serving out there."

Williams, who won 16 of the final 17 points to close out the match, said she had never won that way before.

"That was pretty magnificent," she said. "I've had a bigger comeback -- I was down 6-1, 5-2 and 15-40 and came back to win [over Davenport] in Sydney last year. But it wasn't a Slam. This is my best comeback because it's a Slam."

Kafelnikov's post-match comments were a lot more entertaining than his straight-set victory. With top seed Pete Sampras and defending champion Patrick Rafter having withdrawn from the tournament because of injuries, Kafelnikov made a bold declaration.

"To be honest," he said, "three guys can win the U.S. Open; nobody else has a chance. [Richard] Krajicek, myself and Agassi -- those are the real guys who can win the U.S. Open. Nobody else. . . . I can bet any money you want."

Told of Kafelnikov's comments after his four-set victory, Agassi said, "I don't agree with that. I think anybody who is still in the tournament is a problem."

It appeared that Gimelstob would be a problem for Agassi, but he wound up being more a nuisance. He complained about line calls, flicked a ball into the stands to a fan, and made several emotional demonstrations, all of which drove the crowd in Ashe Stadium to root even louder for Agassi.

"I don't know if I would choose to expend my energy like that because I think you can direct it a bit more efficiently," Agassi said of his opponent's behavior. "I think sometimes when he gets tired on the court it has a lot to do with how much energy he's expending, sometimes between the points."

Agassi is expending his energy playing some of the best tennis of his career. He is practicing harder than he ever has, and telling anyone within earshot that he is no lock to reach the finals just because Sampras and Rafter are out of the field.

"If we could phone in the results, I'm the highest seed left," he said. "But you can't. You've got to go out there and play. All these guys are tough. They all can beat you. I'm certainly aware of that."

U.S. Open at a Glance

Where: USTA National Tennis Center, Flushing Meadows, N.Y.

When: Through Sept. 12.

TV: WUSA-9, WJZ-13, 11 a.m., 5. p.m.; USA, 7:30 p.m.

Defending champions: Patrick Rafter, Lindsay Davenport.

Top seeds: Pete Sampras,

Martina Hingis.

Yesterday's results: See Page D16.

Today's featured matches: Men -- Goran Ivanisevic, Croatia, vs. Gustavo Kuerten (5), Brazil; Magnus Larsson, Sweden, vs. Todd Martin (7), United States; Greg Rusedski (9), Britain, vs. Chris Woodruff, United States Women -- Martina Hingis (1), Switzerland, vs. Arantxa Sanchez-Vicario (10), Spain; Venus Williams (3), United States, vs. Mary Joe Fernandez, United States; Amelie Mauresmo (15), France, vs. Anke Huber, Germany.