Match point for Tim Mayotte. One more first serve. A volley he puts away. The usually stoic Mayotte screams, "yeah," throws his arms into the air joyously and sprints to the net to shake hands.

Waiting for him is Boris Becker. He is staring at Mayotte in disbelief. "What the hell," Becker says to his manager, Ion Tiriac. "Did the guy win Wimbledon or what?"

"Be happy about that, Boris," Tiriac says. "All it means is that the guy respects the hell out of you."

Becker understands, but he still is bothered by it -- after all, this is only a quarterfinal match in the Queens Club tournament. "It's amazing, though, what people are doing when they beat me," he says. "It seems like a very big thing."

It has been 50 weeks since that sun-drenched day when Becker blasted one last serve past Kevin Curren, threw his arms into the air and exulted over being the Wimbledon champion. He had made history, winning at age 17, winning without being seeded, winning although he had won only one other professional tournament, and that one week before Wimbledon began.

Monday at 2 p.m., Becker will return to the spot where he celebrated his victory while the tennis world celebrated him. He will walk to Centre Court to play the traditional opening match as the defending champion. Since he left that court carrying the Wimbledon trophy last July, Becker said he has often thought about that remarkable two weeks.

"It's still rather amazing how -- just like that -- I won Queens and I won Wimbledon," he said recently. "It happened so fast. I had never won, then I won both. It was unusual."

Try extraordinary. Becker's victory, his great presence on court, the vibrancy of his game and his quick smile, made him a star, not just in West Germany but around the world. He has spent the last year coping with the resultant changes as he has become the hunted instead of the hunter and the biggest star in a game that, in truth, he is still learning.

"If you look back at the last year, Boris has done many different things," Tiriac said. "He took his country to the Davis Cup final, he beat the No. 2 player in the world and made the Masters final, he won several tournaments and he beat the No. 1 player in the world to win a tournament.

"All those are additives in the process. But Wimbledon was the noise. It is unavoidable. Now, everybody is saying Wimbledon and Wimbledon and Wimbledon. Can he win Wimbledon again? If he doesn't, it will not be a disaster. He's 18. He's going to win it again."

Some regard Becker's record since Wimbledon as disappointing. In the three other Grand Slam tournaments, he has lost in the fourth round, the second round and the quarterfinals. Twice this year he has lost first-round matches. He has been beaten in the quarterfinals of his last four tournaments.

But, considering all the distractions that accompanied his sudden celebrity, Becker's progress has been good. His ranking, No. 20 in the world before the last Wimbledon, now is No. 5. He has beaten every top player in the world except John McEnroe. And, although he certainly has changed, he has not lost his charm.

After his quarterfinal loss to Mikael Pernfors at the French Open, Becker walked into an interview room to find people fighting for space. Becker smiled. "Have things changed for me?" he asked rhetorically. "Last year I got killed here by Mats Wilander and everyone said, 'Bad luck Boris, see you in '86,' and I left. Now, look at this."

A few minutes later, news conference over, Becker got up to leave. As he headed for the door, he stopped and looked back. "See you in '87," he said. Confidence Never Is Lacking

Becker's future is discussed almost as much as his recent past. He, Stefan Edberg and Wilander are considered the logical successors to Ivan Lendl, McEnroe and Jimmy Connors as the dominant players in tennis.

"When he is on," Tiriac said, "it is a devastating, amazing thing to see. I have never seen a player close, not even close to him when he is on. No one. Some days when he practices, the other guy has to ask him for a chance to hit a few balls. If he just plays normal at Wimbledon, just normal, he will win.

"But he is difficult. He is the most unusual character I have ever met. He is so stubborn. You cannot tell him anything. Everything, he has to find out for himself."

On the court, at 6 feet 2 and 180 pounds, Becker is overpowering, especially on fast courts. He is quick, although his footwork still is a problem at times. More than anything, though, he is tough. "He's a great player on big points," Mayotte said. "That more than anything probably won for him last year at Wimbledon."

Tiriac agreed. His biggest problem with Becker is keeping him from being overconfident in tight situations. "Does he get nervous? I wish," Tiriac said. "He will never choke, because he never thinks he's going to lose a point. Sometimes you have to remind him that he isn't as good as he thinks he is."

This is sometimes difficult for Tiriac. After Becker lost a match in New York in May, someone asked Tiriac how he felt about Becker's progress. "Why don't you go ask him," Tiriac said, "he thinks he's Jesus Christ."

Becker insists that isn't so. "I know I have to work to be more consistent," he said. "When I lost to Mayotte, I was one point from winning he had a match point and I missed a lot of shots I normally make. That tells me I have lots of work to do, but it also tells me I'm on the right track. I am not playing so bad."

Not bad at all. "I think he's dealt with the pressure quite well," Mayotte said. "Most guys have a couple of years to gradually get to the top and get used to being a target. For him, it happened all of a sudden. I'm sure, right now, he's feeling a lot of pressure. The golden year is ending. Now everyone is saying, 'So what happens now?' " A Year of Golden Deals

The past year has been golden, or at least paved with gold, for Becker. Recently, he signed a shoe and equipment contract with Puma that will begin in 1987. Reportedly, he will be paid $24 million over six years for using Puma. He recently signed a deal with Coca-Cola reportedly worth several million dollars and he has a deal with a West German electronics company that produces, among other things, a Boris Becker tape recorder.

He also signed a deal last fall that gave a West German publishing company exclusive newspaper rights to his diaries, first-person pieces and even certain news items, such as his Puma contract. The deal also reportedly calls for three books.

Tiriac, who became Becker's manager and agent two years ago, insists that all this fame and wealth, while enjoyable, is a hindrance to the ultimate goal of making Becker the best tennis player in the world.

"We cannot see the forest for the trees," he said. "Instead of working hours and hours on one thing, we work to get ready for next week. Yes, he is making a lot of money. But the man has no time to breathe, no time to rest. Nothing is easy for him now."

Tiriac leaned forward and lit a cigarette. "I don't think people really understand how important Boris is," he said. "He is not just good for tennis, he is good for the world. He was chosen athlete of the year in Israel last year. Israel! Can you imagine that, a German chosen athlete of the year in Israel? That kind of thing, more than winning tennis matches or making money, makes him important."

Tiriac's handling of Becker's private time has played to mixed reviews. Becker, alone, is eminently approachable. He is still easygoing and always seems willing to talk. But, West German journalists say, Tiriac has overprotected him, hidden him too much.

"Last year everyone said he was fresh and different," Tiriac said. "Now, they say he is cocky. He has not changed that much. But his life has most certainly changed." Changes in Attitude

Actually, Becker is different. On the court, he does not play with the same fearless passion. Now, when things go bad, he might sulk. During the Mayotte match at Queens, when a tendon problem in his middle finger was bothering him, he kept talking aloud about how much the finger hurt.

When Mayotte, after saving match point, took control in the third set, Becker slouched, muttering, holding his head. The relaxed, confident kid of a year ago is no more. Confident, yes. Relaxed, no.

A recent afternoon, as he practiced on a back court at Wimbledon with Wojtek Fibak, Becker twice tossed rackets in disgust and cursed in German after a few bad shots.

Finally, when he dove on the grass to cut off a Fibak shot and hit a cross-court winner, he looked like the Becker of last year. "I hit that shot on purpose," Fibak said, "so I could make you smile."

Becker shook his head. "It's just not fun anymore," he answered. "Not lately anyway."

This kind of behavior doesn't thrill Tiriac, but it doesn't concern him that much either. "He's a little bit like McEnroe because he's a perfectionist," he said.

"I think he's grown up a lot," Tiriac said. "He still gets too emotional, no doubt. But he's more professional this year than last year.

"Last year he won Wimbledon on emotion. This year, he can't do that. He must win on tennis."

Whatever happens at Wimbledon during the next two weeks, Becker knows he never will feel the way he felt last year. He was on a magic carpet ride then, one that protected him from defeat. Joakim Nystrom served twice for the match against him. Mayotte came within two points of victory. Anders Jarryd began their semifinal as if he intended to blow him away. Becker beat them all.

"I want him to be a good No. 1 player," Tiriac said. "To me, that means being a McEnroe or a Bjorn Borg. But look at them. Once they became known, it took them two or three years to get to the top. It will take Boris that long."

Becker doesn't look that far ahead most of the time. "I just want to play and get better," he said. "If I hadn't won Wimbledon, I know my life would be different than it is. But I don't mind the way it is. Because now, no matter what happens, no matter what I do, I won Wimbledon. I can't change that and neither can anyone else."

He smiled and became 18 for a moment. "Of course, I don't want to change it," he said. "I had fun."