Edberg Is Sore About Upset : Semifinals: Gilbert gets the victory in three sets. Swede is treated for a recurring knee injury during match.

Brad Gilbert scored his biggest victory this season and advanced to only his second final of the year as he upset top-seeded Stefan Edberg Saturday at the Volvo Tennis tournament.

Gilbert, seeded fourth, defeated the injured Edberg, 7-6 (7-2), 6-7 (7-1), 6-4, and will face the winner of Saturday night’s match between second-seeded Pete Sampras and Italy’s Stefano Pescosolido.

“It was good to win after eight months,” Gilbert said. “It helps me a lot to play well. I wish I had put it away at 5-4. He played some great shots.”

After breaking Edberg in the second set to go up 5-4, Gilbert was serving for the match when the Swede came back to force a tiebreaker. Gilbert hit the final two volleys into the net, giving the set to Edberg.

Earlier, play was stopped while trainer Bob Norris treated Edberg’s sore left knee.

Edberg said the recurring injury kept him from playing his best.

“I had problems pushing off, which made me a little bit sour today,” said Edberg, playing in his first tournament since Wimbledon. “I had problems pushing off with my forehand, too.

“After it was treated it was better, but I’ve been playing on clay, then grass and now hard court. It’s very tough on your body.”

After winning the second set, he lost only two points and the score went to 4-4. But Gilbert got up a break and went on to win.

“I had a few chances at four-all, then he came back with great forehands and then we’re down to match point,” Edberg said. “If I had gotten the break there it would have been different.”

Gilbert’s previous final this year was at the San Francisco Indoor, where he lost to Australia’s Darrin Cahill.

“What I needed today was to serve well and whack those returns,” said Gilbert, who turns 30 next week. “I figured if I whacked them he’d stay back.”

In the first set of the nearly three-hour match, Gilbert held on to his serve in the 11th game despite trailing 0-40. He fought back three triple-break points and won the game on a service ace clocked at 100 m.p.h. to advance to 6-5.

In the first tiebreaker, Gilbert took a 5-0 lead and Edberg could not regain momentum. Edberg got only 43% of his first serves in during the first set, and Gilbert had two aces.

For the match, Edberg managed to get in only 46% of his first serves.

Edberg holds a 9-4 edge over Gilbert, ranked 19th, and won all three matches the two played in 1990.