NEW YORK, SEPT. 9 -- At 1:54 this afternoon, Lori McNeil stood at the net, bouncing on her toes, as she had so often done during the previous 95 minutes of their U.S. Open quarterfinal, daring Chris Evert to hit a passing shot.

Once, Evert relished such a challenge. She would tee off with her ground strokes and walk away a winner. Not today. Instead of being a target, McNeil was a wall. Now, Evert tried to get one more two-fisted backhand past her, firing the ball cross court.

But McNeil was waiting, and when she snapped one more backhand volley cross court, Evert could only watch. As soon as the ball hit the ground, it became part of tennis history because with that shot, McNeil defeated Evert, 3-6, 6-2, 6-4.

Never before in her 17 appearances in this tournament had Evert lost before the semifinals. Although she has committed to playing a full schedule of tournaments next year, Evert will be 33 in December, she has just finished the first year since 1973 without winning a Grand Slam tournament and she must now wonder if she ever will reach a Grand Slam final again.

Evert has been in 48 Grand Slam semifinals. This will be McNeil's first. She is the first black woman to get that far in this tournament since Althea Gibson won it in 1958.

The loss also blemished one of Evert's most cherished records. Before today, she had failed to reach the semifinals only once in 49 Grand Slam tournaments. That loss came at Wimbledon in 1983 when she lost to Kathy Jordan in the third round.

Evert accepted her loss with grace and dignity, but it wasn't easy. As she and McNeil walked off the court to a standing ovation, she turned and waved to the crowd, the thought perhaps crossing her mind that this might be a farewell.

Once under the stands, she found her boyfriend, Andy Mill, and walked off in a corner to compose herself. Fighting tears, she squared her shoulders, took a deep breath and went to meet the press.

"I was just flat," she said. "Even when I won the first set, I wasn't playing very well. Lori was just making a lot of errors. This is the kind of day you hope never happens to you in a Grand Slam tournament. But when you get older, it happens."

Evert's loss dwarfed good, though losing efforts this afternoon by Pam Shriver and Gabriela Sabatini. Each had chances against the top two seeds in the tournament, but could not convert. Sabatini had a set point on Martina Navratilova, but could not take advantage.

She ended up losing, 7-5, 6-3. Shriver had Graf, the No. 1 seed, nervous after breaking back to 4-all in the first set, but missed three chances to go up, 5-4. "I wanted her to have to serve down, 4-5, with some pressure on her," Shriver said. "She's only lost one match all year because she's steamrollered people. We've all been stupid, not attacking her. I did that today. But I had to get that game to go up. 5-4."

Shriver didn't get it. She double faulted on her third game point and Graf picked up from there, going on to a tough, but convincing, 6-4, 6-3 victory. Navratilova now plays Helena Sukova, who advanced Tuesday, in a rematch of last year's final. McNeil, who turns 24 in December, plays Graf.

"I don't think it will hit me that I beat Chris Evert until next week or something," McNeil said. "Right now I have to concentrate on getting ready for Graf."

Perhaps it was that low-key approach that allowed McNeil to finish. Evert can win matches on the sheer strength of her will, especially matches like this one when all the experience is on her side.

McNeil didn't see it that way. "I felt like the pressure was on her," she said. "The time to beat her is in the quarterfinals. This is only the second time in 50 years that she hasn't made the semifinals of a Grand Slam so this is the round you have a great chance in."

It may seem like Evert has been playing for 50 years, but it is a mere 17. And, when the match started, it seemed as though she could play for 17 more. McNeil looked confused, unsure when to attack, when to stay back. Evert kept her off balance and quickly had the first set.

"I just decided after that, that if I was going to lose, I was going to make her hit passing shots past me to do it," McNeil said. "The first set, I couldn't make up my mind. After that, I was aggressive on almost every point."

McNeil even began to attack on Evert's first serve, and the tactic worked. Sometimes, Evert zinged her with her rocket-like ground strokes. But many other times, those once impeccable lasers were off target.

"I didn't even feel confident on my groundies," Evert said, "and they're my number one weapon. I hadn't played a serve and volleyer before today in this tournament but that's no excuse because I've been practicing with two men. She just played a smart match."

With each passing game, McNeil seemed more sure that she could win. By the time the second set was over, the crowd had come pouring into the grandstand. "When I won that set," McNeil said, "I thought I had a great chance."

It was a strange last set. The server held only once in the entire set -- McNeil in the fifth game. Evert broke for 1-0, McNeil broke back. Evert broke for 2-0, McNeil broke back at love as Evert double faulted three times.

"I knew then that she was really nervous," McNeil said. "I kept telling myself to just be aggressive and try to force her to make mistakes. Even when she broke me back, I kept thinking that if I broke her once, I could break her again."

She did, for 4-2. Evert took a deep breath and played a superb game, hitting four winners in a row. It looked like the old story: McNeil would come close, but . . .

Not today. McNeil broke for 5-3. Boom, Evert broke back. Then McNeil was receiving, needing one more break for the match. At 15-all, she raced in behind a backhand return and watched Evert's backhand sail wide.

Then came the point that said it all. Evert kept McNeil back and when McNeil floated a short backhand, Evert came in, lined up the easy forehand and, incredibly, almost hit the fence on a fly.

"I just never felt smooth," Evert said. "I had no feel. That shot was a perfect example."

It was also match point. McNeil never blinked and, in the flash of a backhand volley, it was over.

For McNeil, all fluid grace and style, this was just a beginning. "Have I arrived?" she asked rhetorically. "Arrived at what? I've made the semifinals. There's still much more to do."