WIMBLEDON, ENGLAND, JULY 4 -- Unseeded Goran Ivanisevic of Yugoslavia came out of a blustering storm to make the semifinals of Wimbledon today. Acing Kevin Curren 27 times over five sets, Ivanisevic was the darling of this strange, damp afternoon, and he is defending champion Boris Becker's dangerous next opponent.

Ivanisevic and Brad Pearce of the United States had similar opportunities in the quarterfinals at the All England Club, but vastly different opponents. Pearce, an unseeded 24-year-old from Provo, Utah, ranked No. 120, met top-ranked Ivan Lendl in a match that seemed utterly hopeless. But he transformed it by stealing a set and making the No. 1 seed fend him off until the end, 6-4, 6-4, 5-7, 6-4.

The 6-foot-4, 18-year-old Ivanisevic did what Pearce could not, seizing the moment to defeat a 32-year-old antique, 1985 finalist Curren, 4-6, 6-4, 6-4, 6-7 (8-10), 6-3. He thus became the first unseeded semifinalist since 1986, and has leaped into the tennis world's consciousness. Five weeks ago he was a curiosity who had upset Becker in the first round of the French Open. Now he is a menace.

"It was a quarterfinal, an unbelievable chance," Ivanisevic said. "Everything is open now. You're going to have a lot of trouble, I think, against me."

The matches were delayed by a rainstorm that swept over the grounds for four hours, the players fidgeting in the locker room. They did not take the courts until 5 p.m., and when they did No. 2 Becker and No. 3 Stefan Edberg of Sweden were sentenced to dicey, windblown outer courts in an effort to get all the matches completed on schedule.

Becker overcame milling crowds and bothersome gusts on the infamous "graveyard of champions," Court 2, and a tricky opponent in No. 7 Brad Gilbert, 6-4, 6-4, 6-1. Edberg, the 1988 champion, was quietly efficient against countryman Christian Bergstrom, 6-3, 6-2, 6-4, to advance to a meeting with Lendl.

"You couldn't play great tennis out there," Becker said. "But I still made the most of it, I kept my cool and I played three solid sets."

Ivanisevic and Curren fought over the right to meet Becker in a match that was more like an artillery exchange. They had advanced this far with some luck of the draw (six seeded men upset in the opening round) and each was loath to let such an opportunity pass. Curren killed a match point in the fourth set and answered Ivanisevic's aces with 16 of his own. Neither dared miss his first serve for fear the other would belt the second into oblivion.

Curren, who was fined $500 earlier this week for kicking and damaging a copying machine in a Wimbledon office when his doubles match was postponed, is best remembered for his appearance in the '85 final against Becker. That was when the 17-year-old rose to preeminence by capturing the first of his three titles. Unwilling to be such a foil again, Curren allowed Ivanisevic to break his serve just three times, but two came in the final set as Curren seemed to tire.

The only service break of the first set came in the last game, as Curren won two rapid volleying exchanges and then struck a textbook forehand passing shot down the line. But that was his only break of Ivanisevic in the match.

He played a courageous fourth-set tiebreaker, recovering from an 0-3 deficit and losing three frustrating set points before clinching it. Ivanisevic delivered his 21st ace for an 8-7 lead and match point, but Curren responded with a bullet serve down the middle, Ivanisevic slipping on the grass and watching the ball go by for an ace. When Curren smashed a service winner for his fourth set point, 9-8, Ivanisevic finally yielded with a backhand volley in the net.

But the Yugoslavian was fresher and generally stronger, with an array of forceful ground strokes, including a two-fisted backhand. He raced to a 4-1 lead with two service breaks, and the sixth game was typical of Curren's difficulties. Ivanisevic forced eight deuces and seven break points before Curren finally held serve. It was his last gasp.

"It was a good chance; I got Curren, not Edberg or Lendl or Becker," Ivanisevic said. "And I say, 'Come on out in the fifth set and give your best tennis. Try,' and I did."

The emergence of Ivanisevic, a fresh-faced brunet from the town of Split who pronounces his name "Ivaneesevich," was not entirely unforeseen. He was a surprise quarterfinalist as a qualifier at the Australian Open last year, and reached the quarterfinals of the French after upsetting Becker last month.

He has a silky game to go with his awesome power and lacks only maturity, frankly admitting that he used to quit when he lost interest or fell behind in difficult matches.

"I'm playing really good and now's my chance," he said. "If I can continue to play like this, I can soon be best."

He was the highlight of an otherwise gloomy afternoon. The courts were slick, players losing their feet easily and often enough that Lendl protested that the matches should be postponed because of the possibility of injuries. He was never completely comfortable against Pearce, who displayed a big serve and some driving passing shots from the baseline as he led by 4-1 in the third set.

Pearce, an all-American from UCLA, is an underachiever who had never won more than two matches in a tournament. Lendl was the first seeded opponent he met here, and he also had to contend with the intimidating surroundings of Centre Court. He comported himself well.

He wrested the difficult third set away after losing his edge, Lendl breaking in the seventh game to put it back on serve, 4-3. He broke Lendl again to take the set in the 12th game, launching a backhand pass across the court.

"I think I have shown not only to myself but to others that Brad Pearce is someone to contend with," he said. "There might be some who say I didn't have the most difficult draw in the world, but you still have to win the matches. A lot of the matches I won decisively. A few points here and there, and it might have been a little different story today."

Gilbert's match with Becker might also have been a different story. He had beaten Becker four times in seven meetings, but never on the grass that so favors the West German. He was irritated by the long wait and the switch to an outer court, where he never warmed to the match.

"I was just a little flat," he said.

Gilbert got what might have been a crucial service break in the sixth game -- the only time he broke Becker -- when he won a breathtaking exchange by retrieving a volley with a flicked backhand passing shot down the line as he rolled to the grass. But Becker broke right back, unreeling three massive forehand winners, and then drilling a fourth that Gilbert wristed into the net with a forehand volley.

Becker got control of the second set in similar fashion, driving returns that forced Gilbert to mishandle them. Gilbert laid two forehand volleys wide to give up his serve in the ninth game and trail, 4-5. Becker broke him yet again in the first game of the final set.

"It just felt like a windy day," Gilbert said. "And that I wasn't getting any breaks."