Tennis is a sport that thrives on nostalgia. Old champions are revered and honored, and so are the traditional venues.

Today at Forest Hills, the former site of the U.S. Open, an aging champion named Guillermo Vilas found some of his past magic in the the semifinals of the Tournament of Champions. And so, too, did Yannick Noah on an afternoon of sun-drenched tennis that left 13,416 and a national television audience panting for more when it was over.

First it was Vilas, playing as if he had stepped from a time machine, reviving memories of 1977, when he won the last Open at Forest Hills. He sliced and slashed his way past fellow Argentine Martin Jaite, 6-3, 6-3.

That should have set up a final here Sunday (WJLA-TV-7, 1 p.m.) against Ivan Lendl, the world's No. 1 player. But Noah had other ideas. Serving superbly, he brought back memories of 1983 -- the year he was the French Open champion -- with a convincing, 6-3, 7-5 victory over Lendl.

This was not the sulking, not-trying Lendl so often seen in defeat. This was a Lendl who grittily saved four match points, who kept searching for an answer to Noah's searing serves and simply couldn't find one.

"I just couldn't do anything to bother him," said Lendl, who won only two points on Noah's serve in the second set. "Any time I tried to do something, he just did it better. My knee bothered recently by tendinitis was fine. He just played better than I did."

Both players wanted this match. Noah had not beaten Lendl since that magic sojourn in Paris three years ago when he became a national hero with his victory. Lendl, using this tournament and next week's Italian Open as warmups for the French Open, certainly did not want to lose to Noah on clay here when he might have to face him on his home clay at Roland Garros next month.

"I just felt very confident against him," said Noah, who lives in New York now and owns a French restaurant in Greenwich Village. "Even when he saved the match points, I felt that the worst that would happen was we would play a tie breaker. The way I was serving, I thought that would be okay."

Noah's serve had Lendl off balance all day. By the end, Lendl was almost in need of an usher to find him a seat he was standing so far back to receive serve. Noah was always the aggressor, taking the net at every chance, forcing Lendl to hit passing shot after passing shot. Some missed. Others, Noah nailed for winners.

"When I am playing well and someone comes in, I feel like I have all sorts of time to choose my spot to pass," Lendl said. "Now, I feel like I have to rush. That's the difference between playing well and not playing well."

Noah played well from the start. They traded breaks early, then Noah broke again at 3-3 when Lendl made a rare advance to the net on break point and Noah crushed a backhand past him. Disgusted, Lendl slammed a ball into the net. That set an emotional tone for the match. Noah won a big point and he did a Jimmy Connors-stoke. Lendl, fighting back, shook his fists a couple times, too.

Noah served out the first set easily and the second set turned taut quickly. Lendl, pressured every time he missed a first serve, needed outright winners to hold serve most of the afternoon. "I thought I put tremendous pressure on him on his serve," Lendl said sarcastically. "What did I win the second set? Two points. Oh, I wonder what happened to him on those. All I could do was hope for a miracle at the end."

Lendl is not known for miracles. Get ahead of him and you're likely to win was once the word. No more. He has learned to hang in even on a day like this when the other guy is better.

Serving at 4-5, Lendl dug an 0-40 hole. Three match points. Time to go home? Hardly. First, a service winner. One point saved. Then a gorgeous topspin lob after Noah came in. Two points saved. Finally, a crisp backhand pass after Noah came in again. Three points saved.

Noah whacked another backhand. Match point four. Another Lendl backhand and Noah was shaking his head. Lendl served out the game and the crowd, one that has jeered him so often in the past, stood to cheer him.

"It made me feel good," Lendl said. "But I still couldn't do anything with his serve." Noah quickly held at love and then had Lendl at 15-40 immediately. This time, Noah was more cautious staying back. This time, Lendl pushed a backhand wide and after almost two hours, it was over.

"It's a good win for me," Noah said. "But I can play better. But so can he."

It isn't likely that Vilas can play better. Nine months ago, when they first played, Jaite, once a ballboy for Vilas, destroyed him, 6-1, 6-0. Today, in the midst of an extraordinary comeback at age 33, Vilas manhandled Jaite. His topspin kept him pinned deep all day and Jaite was never really in the match. "He is much stronger now than last year," said Jaite. "There was no comparison to last time."

Last time was before Vilas had undergone seven months of rigorous physical training -- four hours daily -- for one last comeback. Now, he is in his first final since 1983 and it will come on the same court where he had his finest hour.

"I remember this place as much bigger in 1977," he said today. "But it doesn't matter to me, big or small, I love it. As for age, people have to judge by how they feel themselves. Some people feel terrible when they are 33. I feel great."

And today, he and Noah produced great tennis and great memories.