One day last week, Martina Navratilova, the No. 1-ranked player in the world, asked Leigh Thompson, the 31st ranked player, if she'd like to practice with her before the start of the Virginia Slims tournament in Washington. Navratilova was spending the holidays in Virginia Beach, where she has a new home. Thompson comes from Newport News.

Her coach relayed the answer: a polite no. "He said it was too near the tournament, that she was too nervous," Navratilova said.

"I thought my nerves wouldn't allow me to do what she wanted me to do," Thompson said.

Navratilova shrugged and told her friend, Nancy Lieberman, "You watch, I'll draw her in the first round."

And so she did. On the first point of their first-round match, Thompson, who had never played Navratilova before, double-faulted. Soon the nerves disappeared. But by then, she was behind, 5-0, in the first set. Despite a few patches of unwanted passivity, Navratilova went on to win, 6-2, 6-1.

Next time, Thompson says, she'll accept the invitation.

Andrea Jaeger, the second seed and third-ranked player, did not have it quite so easy. Candy Reynolds forced her to play her best, and as a consequence they played the best match of the day. Jaeger won, 5-7, 6-1, 6-3.

Jaeger wins because she is relentless. But in the first set, the roles were reversed. Reynolds pressed her, pushed her, hitting out. Jaeger is also accustomed to being "the little darling" of the crowd. This, too, was reversed. "If it would have gotten to 5-5 (in the third set), I think, they would have carried her to every ball," Jaeger said smiling.

They cheered when Reynolds broke to go up, 5-3, in the first set, as Jaeger netted a forehand approach. And they urged Reynolds on when Jaeger broke back to make it 5-4 and then held to make it 5-5.

Reynolds, who has never beaten Jaeger, held and Jaeger served to tie it at 6-6. But once again, she fell behind, 15-40. Twice, she saved set points (first with a forehand down the line and then with a service winner). That is the difference between Jaeger and other 17-year-olds.

Reynolds won the set with a lovely forehand cross-court volley but the effort took something out of her. She was tired in the second set. She double-faulted back to back to lose the first game. Jaeger decided to move her around, wear her out. She did.

In the third set, Reynolds struggled to hold serve; Jaeger began to dominate. Finally, in the eighth game she broke through. She won four crucial points in the set with marvelous backhand topspin lobs.

Hana Mandlikova, No. 3 seed, easily defeated Anna-Maria Fernandez, 6-3, 6-0, in a first-round match. Zina Garrison won, 6-3, 1-0, when Claudia Kohde was forced to retire after spraining an ankle during the match.

Sometimes, as Kohde knows, one shot makes all the difference. Certainly, that was the case in Navratilova's match. After going ahead, 5-0, with stunning ease, Navratilova suddenly became "placid." She stayed back too often, tried drop shots that didn't quite work. She double-faulted while srving for the match at 5-1 and squandered two set points in the next game to make it 5-2. Again she served for the set, again she fell behind, 30-40, before holding to win.

Now, Navratilova appeared a bit unnerved, if only at herself. In the first game of the second set, Thompson, who was looking stronger, hitting out, went ahead, 40-15, on her serve. Then came the shot. Navratilova was on the defensive, as she had been for the last two games. Thompson hit an overhead, by no means a bad one, wide to Navratilova's forehand. "I didn't think I could get to it," Navratilova said.

Somehow, she did. Somehow, she reached it with her forehand, and the ball, which was headed for the stands, curved around the net post, and down the line for a winner.

Navratilova won the next four games and the set, giving up only one point on her serve. "If I had won that point . . . " Thompson said, shrugging. "I don't even know how I lost it. I had a chance to go ahead. Maybe, she plays different when she's behind."

"I knew it was time to do something spectacular," Navratilova said, laughing. "But I wasn't planning on it."