Andre Agassi and Pete Sampras are eyeing each other from across the grass at Wimbledon. On opposite sides of the draw, they are not yet ready for a showdown, but they got a step closer today when each advanced to the semifinals at the All England club.

Agassi earned his spot by delivering a focused 6-3, 6-4, 6-4 victory over Gustavo Kuerten, ignoring the circus-like atmosphere that follows the Brazilian wherever he goes. Sampras's road to the semifinals was shorter but more nerve-racking: the five-time Wimbledon champion was down a set to Mark Philippoussis when the towering Australian lunged for a backhand and tore cartilage in his knee. Philippoussis had to retire, giving Sampras a 4-6, 2-1 win, but the experience -- which included Sampras double-faulting three times in his opening service game -- left the 28-year-old feeling frustrated.

After the match, he blamed his rustiness on the multiple rain delays that have plagued the second week of the tournament.

"I can't say I really fended off Mark today, I mean, he was outplaying me," Sampras said. "I can't sit here and feel very good about it.

"Not having played that much this week showed today, but I feel all right now, and I'm pretty fortunate to be alive in this tournament. Tomorrow is going to be even more difficult, playing Tim Henman, but I'm looking forward to a good match."

To get an all-American final on the Fourth of July -- something that last happened when Sampras defeated Jim Courier in 1993 -- Sampras must get by No. 6 seed Henman, who defeated Cedric Pioline today, and Agassi must get by No. 2 seed Patrick Rafter, who beat Todd Martin. Neither will be an easy match, and both will be complicated by the weather, which changed faces yet again today by draping the grounds with sunshine.

The clear skies allowed the quarterfinals in both draws to be completed, with 18-year-old American Alexandra Stevenson and 17-year-old Croatian Mirjana Lucic each advancing on the women's side to join Steffi Graf and Lindsay Davenport in the semifinals. With so much of the tournament wiped out by rain, organizers must hope the storm clouds predicted for Saturday pass over if they are going to get all four semifinals completed. Currently, the men's and women's finals are planned for Sunday, but any delay would push one or both finals to Monday.

The condensed schedule has forced Davenport and Rafter to drop out of the doubles draws, with Rafter feeling his 6-3, 6-7 (7-5), 7-6 (7-5), 7-6 (7-3) win over Martin was more than enough of a workout for the day. Henman also needed four sets in his 6-4, 6-2, 4-6, 6-3 win over Pioline, who was so loose he started dancing to some music at one point in the match. Of course, the English fans drowned out almost any other noise as Henman continued his quest to become the first British man to win here since Fred Perry in 1936.

Henman has held up remarkably well under that enormous pressure, although he will have a Herculean task against Sampras, who beat him in the semifinals here last year and holds a 5-0 record in their head-to-head matches. Henman almost got the better of Sampras earlier last month at Queen's Club, a grass-court tournament, but Sampras fought off break points in the third set to win the final in a tiebreaker.

The two have yet to discuss that match, Henman said, although they have gone golfing together since then.

"There's no comparison; he's a much better golfer than I am," said Sampras, who has developed a close friendship with Henman over the last three years. As for tennis, "I know his game well and he knows my game well because we've practiced together. There's no question that with Tim, it's just a matter of time before he breaks through and wins here. Hopefully it just won't happen this year."

Sampras can tie Roy Emerson's record of 12 Grand Slam titles if he can get through his next two matches, although the victories by Rafter and Agassi today ensure that he will lose his No. 1 ranking whether he wins Wimbledon or not. Because Sampras got off to such a poor start this year -- Queen's was his first title -- either Rafter or Agassi can pass him in the rankings by winning Saturday.

Rafter, ranked No. 2, has been playing excellent tennis, running down balls with ease and volleying with precision. This is the first time he has advanced past the fourth round, however, giving Agassi the edge in experience. Agassi, the 1992 Wimbledon champion, has also been sharp. He kept Kuerten under control throughout their match today.

That wasn't easy to do with the carnival atmosphere created by Kuerten's cadre of yellow-and-green clad fans, although Agassi did a better job of blocking out the commotion than he did in 1987, when he won his first tournament title in Itaparica, Brazil.

"I played Luiz Mattar [in the final] and won, but the place was going nuts," he said. "I remember a lot of women in dental-floss bathing suits just sitting in the crowd. It was very distracting. Once I got past that and started looking at Mattar, it was a step down visually, but I felt the match got a lot better."

CAPTION: Pete Sampras, above, wins when Mark Philippoussis hurts his knee in second set. Andre Agassi beat Gustavo Kuerten.

CAPTION: American Alexandra Stevenson curtsies after 6-3, 1-6, 6-3 win over Jelena Dokic. Stevenson became the first qualifier in Wimbledon history to reach women's semifinals.

CAPTION: Up next for Andre Agassi, above, is Patrick Rafter, a 6-3, 6-7 (7-5), 7-6 (7-5), 7-6 (7-3) victor over American Todd Martin. Tim Henman beat Cedric Pioline.