WIMBLEDON, England, June 29 — Pete Sampras has been humbled in 1998 — he has lost the No. 1 ranking briefly, has failed to do much in the major tournaments, and he has won only two lesser titles for the year. Here at the All England club, though, Sampras had no reason to think he still would not reign as king. Here on the grounds where he has won four titles — including last year's — Sampras understandably expected to be treated with the reverence and respect that has come to be his due.

Richard Krajicek, however, has chosen to demur. On a day jam-packed with tennis (and only briefly delayed by rain), Sampras and Krajicek both won their third-round matches and marched another step toward what could be an intriguing men's final between the world's No. 1 player and the only man who regularly gets the best of him. And Krajicek — who has taken to referring to Sampras as "number 10 in the world" — would like nothing more.

"From January 1, he is number 10," Krajicek said, dismissively. "Even though he's ranked number one, that's because he had a good run at the end of the year, and he's won Wimbledon. But he knows it himself, that he has not done so well."

Krajicek, the No. 9 seed, completed his third-round match with Germany's Nicolas Kiefer with a straight-set victory, and Sampras capped off a 6-3, 7-6 (7-4), 7-6 (7-3) victory over Thomas Enqvist, as Wimbledon finally finished up third-round play and started the fourth.

No. 12 Tim Henman, England's own heartthrob, became the first man to advance to the quarterfinals when he upset No. 6 Patrick Rafter, 6-3, 6-7 (3-7), 6-3, 6-2, in front of a joyful Centre Court crowd early this evening, and he was joined there by No. 3 Petr Korda. Korda, who meets Henman in the next round, valiantly finished off John van Lottum despite injuring his left ankle in the third set. Limping, Korda won a game at love to set up a third-set tiebreak, then screamed in relief when he escaped with the straight-set victory.

For the women, No. 2 Lindsay Davenport, No. 6 Monica Seles, No. 16 Nathalie Tauziat and unseeded Natasha Zvereva — who upset Steffi Graf last week — all advanced to the quarterfinals, and no seeded players lost in the third round.

Monica Seles waves to the crowd after defeating Sandrine Testud. (Kevin Lamarque/Reuters)

Despite the success of the seeds, though, the woman's draw lost some of its flash when 16-year-old Serena Williams pulled out in the second set of her third-round meeting with Virginia Ruano Pascual, citing a leg injury. Serena's departure short-circuited a much-anticipated, fourth-round meeting between the Williams sisters — Serena and older sister Venus — and instead left Venus, who won in straight sets today, to face Ruano Pascual.

Serena slipped and fell on her left leg in the first set of the match but continued play into the second — her left calf wrapped in a bandage — before choosing to bow out for fear of a longer-term injury. Ruano Pascual led, 7-5, 4-1, at the time.

Venus "might go a long way, since now I'm out of the draw," said Serena, who precociously announced that she had expected to "go all the way" at this Wimbledon. "We'll have to see. I'll give her some tips."

Brash as she was, Serena had nothing on Krajicek, who calmly suggested that Sampras needs to work harder and up his level of motivation if he hopes to finish on top again this year.

"He has to start working and wake up to what everyone has said," said Krajicek, who beat Sampras in the quarterfinals during his run to the Wimbledon title in 1996 and has a 4-2 career edge. "He has to start winning some tournaments, because the [two tournaments Sampras has won this year] are smaller tournaments, and in the slams he hasn't done too much. The fact is, since January 1st, Marcelo Rios is leading by a long way, and Sampras is about 10 or 11 in ranking."

Krajicek's remarks marked the second time in five days that he had questioned the usually unassailable Sampras. Thursday, Krajicek suggested that Sampras "is not as motivated as he normally is" and said that Sampras was going to find it "very difficult to keep the number one spot."

None of Krajicek's comments can be considered anything but accurate, but after winning 10 Grand Slams and finishing five straight years as the No. 1 player, Sampras is not used to hearing others do anything but praise him. And so he took a big gulp of water and smiled wryly before he commented on Krajicek and his opinions.

"That stuff really doesn't faze me," Sampras said, though he looked anything but pleased. "I know my capabilities. I know how I'm playing this week."

Sampras has not lost a set through the first three rounds, and his next opponent — France's Sebastien Grosjean — is a qualifier who got this far by upsetting No. 16 Felix Mantilla today. Against Enqvist, Sampras never had his serve broken, served 29 aces and saved three set points in the third.

But things have been nearly as smooth for Krajicek, who has the added benefit of playing in the now nearly seedless bottom half of the draw. The only seeded player between the Dutchman and a potential meeting with Sampras in the final is No. 14 Goran Ivanisevic, who also won a third-round match today. Krajicek and Ivanisevic — two grass-loving, big-serving players — could meet in the semifinals this week.

"I know people are talking about it," Krajicek said playing of Sampras for the title. "I think I have a good chance of doing something very nice here. But I don't want to think too much of the final."