The storm clouds that rumbled around the outer edges of London over the weekend finally charged through Wimbledon today, sweeping more than half the tournament's fourth-round matches off the court. The weather kept many of the marquee players from playing at all, but Australian qualifier Jelena Dokic was able to squeeze enough tennis between the raindrops to continue her incredible run here with an upset of No. 9 seed Mary Pierce.

The 6-4, 6-3 come-from-behind victory puts the 16-year-old into the quarterfinals, along with seeded players Andre Agassi (4), Lindsay Davenport (3) and Jana Novotna (5), who also won today. British favorite Tim Henman had a 4-6, 7-5, 7-5, 4-3 advantage over Jim Courier when rain interrupted. Second-seeded Steffi Graf was stopped midway through a 6-2, 4-2 drubbing of Belgium's Kim Clijsters. The match between No. 6 seed Venus Williams and No. 17 seed Anna Kournikova and the match between Boris Becker and second-seeded Patrick Rafter were both postponed.

Water-soaked fans roamed around the All England club grounds long after play had been suspended for the day, perhaps hoping for a last-minute reprieve, although those who had seen Dokic's victory seemed plenty satisfied. A crowd favorite since dispatching top-seeded Martina Hingis in the opening round, Dokic proved herself to be more than just a one-upset wonder by defeating Pierce, who is a much stronger hitter than any of the other opponents she has faced.

"This was a big match for me, with Mary being a top 10 player and a seed here," said Dokic, who practiced with Graf this morning to get the feeling of playing a more powerful ball striker. "Beating Hingis is still in my head. I'm thinking, `Well, did that really happen? Am I able to beat top players?' Then beating Mary today sort of proved it for me."

Dokic got off to a slow start, falling down 0-3 in the first set before finding first her service game and then her fearsome forehand. Her booming groundstrokes and wide, feisty facial expressions quickly vanquished any frailty suggested by her stick-like arms and legs. Once Dokic found her power, the more muscled Pierce fell further and further out of contention.

Dokic won five games in a row to close out the first set, and sat on serve in the second until Pierce double-faulted to give her a break at 4-3. She broke again to win the match, hitting a dart-like forehand winner that Pierce could only watch fly by.

"It was tough to get off to a good start, because I didn't know what to expect from her," Dokic said. "But once I got in a few games I really got fired up and got going."

After the match, Pierce said she made too many mistakes when selecting shots, although she abruptly cut her media conference short when a reporter asked about her use of Creatine, a legal but controversial training supplement. Pierce said earlier in the tournament that she used Creatine for two brief periods last year and found it helped her endurance.

Henman, seeded No. 6, has also said he has tried Creatine but he has not been hounded by the same questions as Pierce, with the focus here instead funneling toward his match with Courier. The contest is a rematch of one of the Davis Cup matches England lost to the United States in April, and Henman went into the match "desperately" wanting some revenge. He seemed to be close to getting it when rain chased the players off the court, although the match had been suffocatingly close to that point and remained on serve in the fourth set.

Agassi had a little more breathing room, finishing off qualifier Wayne Arthurs, 6-7 (7-5), 7-6 (7-5), 6-1, 6-4, although it took him until the third set to break the Australian's serve. Recognized as the best service returner in the game, Agassi isn't accustomed to waiting that long, but Arthurs was on quite a roll as the only player to reach Wimbledon's second week without having his serve broken.

When Agassi finally pushed through in the third set, Arthurs's streak was halted at 111 games. Finally being broken seemed to rattle Arthurs, who lost three straight service games and any hope of winning the match.

"It was definitely my greatest challenge so far, because I hadn't faced any big servers yet, let alone a lefty, let alone a serve-and-volleyer," Agassi said. "This was a dangerous match for me. I gave him that kind of respect going out there, and I was glad I did.

"But I didn't expect the versatility in his serve. I mean, he's an Australian, so if he didn't know how to serve and volley well they'd take away his passport, but I wasn't expecting him to hit all the speeds in every corner of the service box."

Agassi will next face Brazilian Gustavo Kuerten, who has almost as big a cheering section following him around as Agassi. Usually dismissed as a clay-court specialist, the 11th-seeded Kuerten has looked sharp throughout the tournament, defeating Lorenzo Manta, 7-5, 6-4, 5-7, 6-3, today.

"I've never been in the quarterfinals here, and so it's going to be a lot of fun," said Kuerten, who won the French Open in 1997. "Hopefully he won't hit too hard and he'll let me play and enjoy myself a little too."

Wimbledon 1999

When: Through July 4.

Where: All England club, Wimbledon.

Defending champions: Pete Sampras, Jana Novotna.

Top seeds: Sampras, Martina Hingis.

Today's TV: 10 a.m. WRC-4, WBAL-11; noon and 7 p.m., HBO.

Yesterday's results: Men -- Andre Agassi (4), United States, def. Wayne Arthurs, Australia, 6-7 (5-7), 7-6 (7-5), 6-1, 6-4; Gustavo Kuerten (11), Brazil, def. Lorenzo Manta, Switzerland, 7-5, 6-4, 5-7, 6-3.

Women -- Lindsay Davenport (3), United States, def. Barbara Schett (14), Austria, 7-6 (9-7), 6-1; Novotna (5), Czech Republic, def. Nathalie Dechy, France, 6-3, 7-5; Jelena Dokic, Australia, def. Mary Pierce (9), France, 6-4, 6-3.

Yesterday's suspended matches: Men -- Tim Henman (6), Britain, leads Jim Courier, United States, 4-6, 7-5, 7-5, 4-3; Cedric Pioline, France, leads Karol Kucera (13), Slovakia, 6-4, 5-7, 7-6 (7-5), 1-0. Women -- Steffi Graf (2), Germany, leads Kim Clijsters, Netherlands, 6-2, 4-2; Nathalie Tauziat (8), France, leads Dominique Van Roost (15), Belgium, 6-3, 0-1; Tamarine Tanasugarn, Thailand, is even with Mirjana Lucic, Croatia, 5-5.

Today's featured matches: Men -- Sampras (1), United States, vs. Daniel Nestor, Canada; Boris Becker, Germany, vs. Patrick Rafter (2), Australia; Courier, United States, vs. Henman (6), Britain; Todd Martin (8), United States, vs. Goran Ivanisevic (10), Croatia; Greg Rusedski (9), Britain, vs. Mark Philippoussis (7), Australia. Women -- Clijsters, Belgium, vs. Graf (2), Germany; Venus Williams (6), United States, vs. Anna Kournikova (17), Russia.

CAPTION: Australian qualifier Jelena Dokic upsets No. 9 seed Mary Pierce, 6-4, 6-3, after trailing 0-3.

CAPTION: Jim Courier departs Centre Court after rain disrupted his fourth-round match against Britain's Tim Henman, who was leading, 4-6, 7-5, 7-5, 4-3.