She walked effortlessly through the crowd, just another healthy, blond girl in a clean, white T-shirt and a pair of blue satin short shorts. Nobody stopped her. Nobody gave her a second look. Why would they? She was nobody special. Not yet, anyway.

But the day is almost here when she won't be able to walk so freely through a U.S. Open tennis crowd, when her face won't seem so forgettably common, or as easy to pass by. Just as sure as dew on an autumn morning, her time is coming.

Maybe in two years.

Maybe in six months.

Maybe today, if she could only beat Martina Navratilova.

Steffi Graf is 16, and she's taking all the balls on the rise. By 18, by 19 at the latest, they say, Graf should be a champion. Like Chris Evert was.

Of course, by 21 she could be gone. Like Tracy Austin and Andrea Jaeger.

It's called "burnout."

From Cy Young to Sayonara.

The Grafs, Steffi and her coach and father Peter, are standing in a hallway near the players' lounge saying that it won't happen to her. It can't. He calls the shots, and he won't allow it.

"I don't play too many tournaments," she says. She looks over at her father, a young man himself at 46, and says proudly, "My father is doing it very well. If you have a good timetable, I don't see how you can get burned out." And anyway, she's saying, maybe a touch impatiently because she's getting worn out by this subject already, not everyone burns out; hardly anyone, really, when you look at the total picture. "There's so many players, and there's just two who did," she says. So what's the big deal? "It's their decision. They just didn't want to play anymore."

It's all so simple when you're 16. She smiles and says cheerfully, "I like playing tennis. It's important to really like it. If you really want to play, you should."

Peter Graf is listening for the magic words -- if you really want to play, you should -- and when he hears them, he shakes his head and grins. No, his daughter doesn't play too many tournaments, only 10 so far this year. (By contrast, the other much-regaled Baby Boomer, 15-year-old Gabriela Sabatini, has played in 21). But young Graf would if she could.

It has been said that Andrea Jaeger's father-cum-coach contributed mightily to her tortured exit by forcing her to practice when she didn't want to. "I don't know how hard and how strong Andrea's father pushed her," Peter Graf says. He looks at his daughter in wonderment and says, "I've never had to push her to play, never had to ask her to practice. I have to tell her to stop."

This is a difficult double, he admits, being a coach and a father; you are never certain where one role ends and the other begins. When the roles conflict, which one is dominant? But Peter Graf is pleased that he can play both roles. He would not, under any cicrumstances, have given his teen-age daughter over to a coach and an obsession, sent her to a foreign country to train the way Sabatini's parents have. "It's not good," he says, a slight shudder in his voice. Putting his index finger to the side of his head, he says, "It's not good for up here."

Yes, he says, he favors the new rules the Women's Tennis Association is adopting that will limit the number of tournaments the Baby Boomers can play, rules specifically designed to combat the acceleration of burnout. These are good rules, he says, good for the body, the mind and the soul. A child who is too soon taken -- even a supremely talented child -- is too soon gone.

At ideal times, there are four back home in West Germany: mother, father, Steffi and her 14-year-old brother. "All our family is for Steffi. We do all we can to have much for her at home. At home it is always same as Christmas," Peter says wistfully. "But more than one week at home, she likes to go to tournaments." He shrugs, and there is resignation in the gesture. "That is her life."

He says that he knew long ago, when she was just 5 years old, that she could be something special with a racket in her hand. "She could concentrate on the game for hours; I thought that was impossible," he says, and he is still bewildered by his daughter's gift. Her gift became his responsibility, and they seem to have come through it well. So far. She has not chafed under his tight hold. As he has tried to be both coach and father, she has tried to be both student and daughter. She looks at him fondly and delights in helping him with his English, which is less than hers. He looks at her respectfully, gratified to be able to honestly say, "She is not a star. She doesn't go around with her nose up. She is a normal child, you know what I mean?"

Burnout, they say, won't happen to them. They've got it under control.

We have heard this all before.

So we wait, and we hope, and sometimes, perhaps, ever mindful that it could happen to us, we pray.