One moment he was blowing kisses and screaming, "I love you," to 7,000 people. The next he was running to his yellow Rolls-Royce, ducking out of the National Tennis Center as quickly as possible.

They are calling Vitas Gerulaitis names these days. Some are unprintable. Others include: rude, insufferable, impossible and enigmatic. Gerulaitis has heard it all. He has heard people say he can't play tennis any more. And so, at age 27, Vitas Gerulaitis came to the U.S. Open this year with a lot to prove: to the press, to the fans, to the other players. And to himself.

"There was a time when I began to wonder if all these people who were ragging on me were right," Gerulaitis said Monday after his five-set upset of third-seeded Ivan Lendl. "I just wasn't keen for tennis at the beginning of the year. I didn't want to do the work, run down the ball, stay out there when I had to.

"People have written me off, a lot of guys who I thought were my friends have gone out of their way to rip me. So my attitude now is the hell with them."

By "people," he means, for the most part, most of the tennis press. He has refused to come to mandatory postmatch interviews for months, and says he will come to one only if he loses here, not if he wins.

"I'll take the fine ($500) every time. I don't need the money and I don't need the press, either," Gerulaitis said in a telephone interview Monday night from his home in Kings Point, N.Y. "If I win the tournament I'll take the $60,000 and give it to some bum on the street or something.

"I'm beyond doing this for the money. I don't have to play all that well to make a lot of money. I'm doing this now for the prestige, that's all. They can fine me all they want."

Even in victory Monday there appeared to be little joy in Gerulaitis. He was ecstatic for that brief moment at the end of the match when he stood and blew the kisses.

Moments later though, after telling an official from the U.S. Tennis Association he would come to the interview room after showering, he was on his way off the grounds, almost running to his car. Once people were a delight for him; he now avoids all but a few select friends and his family.

"This is only one match. I'm not going to get that excited about it," he said. "It shows me I can still do it, that I've still got it and that's great. But I've got a long way to go in this tournament."

It is not unrealistic for Gerulaitis to think in terms of winning here. He has won two Italian Opens, an Australian Open and a WCT title. He has also reached the final of the French and lost the final here two years ago to John McEnroe.

But he has not been able to beat Bjorn Borg. Even though he and Borg are close friends and practice together frequently, Gerulaitis admits that his inability to beat Borg (0-20) had as much to do with his slide as anything.

"I got to Connors, I got to McEnroe but I just couldn't get Borg," he said. "It got frustrating. I just got tired of chasing, chasing and not getting there. I took time off because I wanted to get away from tennis for a while and when I came back I didn't have the mental toughness I needed. I started losing matches I had taken for granted and I dropped on the computer.

"I had to decide if I wanted to do the work to come back. I hadn't had Fred Stolle with me for most of the year and that hurt me. Fred was the one who made me work hard, gave me discipline. Now he's back and that makes a difference."

It was Stolle, a former U.S. Open champion, who leaned out of the stands between the fourth and fifth sets Monday and told Gerulaitis, who had been arguing continuously with chair umpire Herb Kosten, to stop it and play tennis.

Gerulaitis calmed down, began playing tennis again and raised the level of his game high enough to beat the world's No. 3 player.

"He's still got all the shots, he can still hit the ball as well as anyone in the world," Stolle said. "It's just a matter of self-discipline . . . He can still do that if he wants to. The key is wanting to do it."

Having reached a plateau as the world's No. 4 player, Gerulaitis lacked the incentive he needed to work at his game. He had become a superstar, literally the golden boy of tennis with his flowing blond locks, his disco-king life style and his expensive cars.

He was rich, the money was rolling in, but no matter how hard he worked, he could not beat Borg. Now, counted out, Gerulaitis has incentive again.

Still, he barely survived his first match here against Terry Moor, who came up with some celestial passing shots to split four sets.

"His whole game is confidence and he hasn't been playing confident lately," Moor said after losing the fifth. "You have to keep him from winning a couple of great points with those gets of his because that's what builds his confidence."

With his quarterfinal match against unseeded Bruce Manson Wednesday, people are suddenly talking about a semifinal against McEnroe. Quickly, it appears, Gerulaitis has reclimbed the mountain.

"I'm glad for him," McEnroe said. "It's good to see Vitas come around. He's a really good player and you don't like to see a guy with talent not playing up to it."

But if Gerulaitis has won back respect on the court, the same can't be said off the court. Once known as one of the game's nice guys, a player who took time to work with kids, someone who always was accessible, who would talk about Borg, Connors or McEnroe as quickly as he would about himself, he is persona non grata with the tennis media and less than overwhelmingly popular with the fans.

Once Gerulaitis would linger to sign autographs, to talk with people after a match. Now he sprints to the locker room, then sprints from the locker room to his car. He has a small, select group of friends and that is it. After his win over Moor, he was ignored in the locker room while other players gathered to offer Moor condolences.

"I've learned a lot about people from this experience," Gerulaitis said. "A lot of people who used to come around and slap me on the back and be my buddy changed when my game went down. I don't think I've changed. I don't regret it, though, because I've weeded out a lot of people.

"I've gone back to the drawing board with my game and with my life. I know I'm only going to have a chance to play this game really well for maybe three, four more years and that's all I'm worrying about now . . .

"I've gone through a period that almost everyone goes through at some point, a lull. I've learned one thing from it: how quickly they forget. I'm past the stage of caring what people think or write about me. Today, when I won, I almost felt like crying out there because it had been so long since I've felt the crowd behind me like that. It was an unreal feeling.

" Coming back when people said I couldn't is a hell of a feeling."

The feeling was one of joy, that was clear after match point against Lendl. It was also a feeling of vindication. "The boy is back," Gerulaitis said in a brief interview in the parking lot, flashing the smile that once won hearts. "Tennis is fun again."

With that he was off, driving into the solitude he once shunned.