Pitted against a Parisian teenager playing her first pro tournament on grass, Serena Williams was never threatened at Wimbledon on Tuesday. So there was no need for the defending women's champion to flex her formidable muscles -- particularly after bolting to a 6-2, 3-1 lead against a wide-eyed Tatiana Golovin, who had never set foot on Centre Court before.

But with the chance to go up 4-1, Williams ripped off the fastest serve ever recorded by a woman at the fabled venue. The courtside speed gun read 126 mph. The statement it made was even bigger: Williams was not about to be upstaged by a 16-year-old and certainly not at Wimbledon, where she hasn't lost a singles match since 2001.

With the 6-2, 6-1 victory, Williams advanced to Wednesday's quarterfinals, where fellow American Jennifer Capriati awaits a reprise of the French Open quarterfinal just three weeks ago. Capriati won that encounter on the red clay at Roland Garros, 6-3, 2-6, 6-3, only to be bounced in the next round by eventual winner Anastasia Myskina.

It was Capriati's second consecutive victory over Williams following eight losses. Their meeting Wednesday, easily the most compelling of the women's quarterfinals this fortnight, should go a long way toward clarifying who is the stronger player.

Both are finally fit and in form, with Capriati rebounding from a back ailment and Williams showing no lingering effects of last summer's knee surgery.

Neither has dropped a set this tournament, though Capriati struggled more than Williams in her fourth-round match Tuesday before prevailing over Nadia Petrova, 6-4, 6-4.

And both desperately want to embellish already sterling Grand Slam records. Williams is chasing a third consecutive Wimbledon title; Capriati, 28, has never won here and knows time is running short to diversify a portfolio that includes two Australian Opens and one French.

Fellow American Lindsay Davenport, who advanced to the semifinals with a 6-2, 6-2 victory over Karolina Sprem, believes the faster grass surface will give Williams a slight edge over Capriati.

Three-time Wimbledon champion John McEnroe is rooting for Capriati. "It'd be a great cap to her career," said McEnroe, now an NBC commentator. "She's been through so much, and she came back and won those majors and got herself to the top of the game."

But regardless of preference or prediction, tennis insiders are rooting for a close match, hoping that a sizzling next installment in their rivalry will jump-start waning interest in the women's game.

That's because the glorious eras of tennis have all revolved around great rivalries: McEnroe and Borg on the men's side; Evert and Navratilova on the women's. And while the arrival of Venus and Serena Williams injected enormous excitement in the game, their matches against each other have understandably lacked the venom and ruthlessness that give the best rivalries their bite. How could one sibling's victory over another not be tinged with remorse or ambivalence, at the least?

But if journalists were eager to play up longstanding rumors of tension between the two on the eve of Wednesday's quarterfinal, Williams and Capriati were having none of it.

"I think she respects my game, I respect her game, and that's basically it," Capriati said. "And as far as personality, I mean, we're not like the best of friends, but we're not like enemies, either. I mean, I get along with everybody."

Williams said she never had a problem with Capriati and blamed reports to the contrary on an American tennis commentator whom she declined to identify. "I'm always professional," Williams said. "I never had a problem with Jennifer."

Like McEnroe, Williams spoke admiringly of Capriati's ability to come back and win three Grand Slams after a mid-career layoff. She went on to praise her as a great athlete, able to hit the ball with pace from any spot on the court. "I think we're both really good athletes out there," Williams added. "We really are able to contort our bodies and just make the shots. Even if we're in the wrong position, we're able to get different balls."

Both Capriati and Williams are known for their aggressive styles, relentless in dictating the pace and tempo of the match. Both have well-earned reputations as fighters, too, able to summon that extra bit of power when all looks lost. So Wednesday's match may look a bit like two dancers doing a tango, with both determined to lead.

Davenport predicts a close match, with the hard-serving Williams benefiting from the fast surface and Capriati riding a wave of confidence from her victory in Paris. "She's definitely going to make Serena play," Davenport said of Capriati. "I think it's up to Serena -- how consistent she is with her groundstrokes and how well she serves."

As for Williams's 126 mph serve, Capriati wasn't fazed. Asked about the new Wimbledon mark, Capriati just smiled and said: "It really doesn't matter. Maybe the radar's off, I don't know."

Serena Williams, serving to Tatiana Golovin, set women's Wimbledon mark with 126 mph serve."I never had a problem with Jennifer [Capriati]," says Serena Williams, defusing talk of tension between them."She respects my game, I respect her game," says Jennifer Capriati, who beat Williams at the French Open.