It was a big night for spectators at William H.G. FitzGerald Tennis Center yesterday evening, as fans got to see three American Grand Slam winners — Chang, Courier and Agassi — in one session under the lights on Stadium Court. Agassi led the parade with his quarterfinal against Sebastien Lareau, and proved to be an entertaining (if quite brief) warmup act with a 6-1, 6-2 victory. Then Chang and Courier finished the night with a baseline duel that Chang won, 6-3, 6-4, after stymieing Courier with his on-court acrobatics.

The two matches completed the field for today's semifinals, which will pit Agassi against South Africa's Wayne Ferriera, a 6-4, 6-7 (7-3), 6-1 victor over American Vince Spadea yesterday afternoon. Chang will play Australia's Scott Draper — who upset fifth-seeded Filip Dewulf, 6-3, 6-2 — in the second semifinal tonight.

Together, Chang, the No. 1 seed, and Agassi, the No. 2, have won five of the last eight tournaments here, and neither has dropped a set this week.

"Things seemed to go really well," said Chang, who has won 15 straight matches in Washington, counting his two Legg Mason titles, in 1996 and 1997, and his two victories in Davis Cup play last fall. "I was pretty focused and everything seemed to flow."

The same could be said for Agassi. When he's focused — and when he's moving well on the court — Agassi feels capable of accomplishing anything, and this appears to be one of those times. Last night, his domination of Lareau was so complete that the crowd practically demanded that he not only win, but win them free bagels to boot.

After hearing over the public address system that all ticket holders would get a bagel from a local bakery if any set ended 6-0, several fans were yelling "bagels! bagels!" at Agassi after he went up 5-0 in the first set without having to flex more than a few muscles. To the crowd's dismay, though, Lareau held serve in the sixth game before Agassi closed out the first set.

"I needed a little help to get them the bagels," Agassi said. "You can't expect to beat anybody 6-0."

Agassi's entire match took a mere 56 minutes, and that included a brief delay as one of the linesmen attempted to repair a pair of broken eyeglasses. Dismayed by the unexpected interruption, Agassi stood over the poor soul and tapped his foot in mock impatience as the man tried — in vain — to pop his lenses back into place. And, after the match was over, Agassi was happy to make up for the brevity of his on-court performance by chatting with the crowd.

"Choose your opponents well," Agassi advised, when asked how the average fan could duplicate his success. "And you'll be okay."

After Agassi's departure, the crowd settled in for Chang-Courier, and the two Americans did not disappoint.

In a match far more competitive that the score might indicate, Chang broke Courier to go up 4-2 in the first set, held serve for 5-2, but couldn't convert two set points on Courier's serve. And when he did win that set — in the next game — Chang did so in the most incredible of circumstances: He ran toward the baseline, with his back to the net, and his was racket pitched downward in what looked to be little more than a desperate attempt to produce some semblance of a return.

Desperate it might have been, miraculous it was. To Courier's disbelief, Chang managed a cross-court winner, a shot that neatly skimmed just inside the line and bounced wide. Stunned, Courier threw up both his arms in a gesture of acquiescence, then jogged to his seat with a bemused smile on his face.

"I've never made a winner off a shot like that in my life," Chang said. "I take no credit for that at all."

By the middle of the second set, Courier no longer was amused by Chang's seeming ability to reach any shot, anywhere, and instead grew openly frustrated — both with Chang, and with his own inability, as he yelled to himself, to "hit the ball straight!" All around, Courier was stymied by Chang, who seemed to have every aspect of his game on a roll, starting with his serve and ending with his ever-amazing ability to cover the entire court.

"I got a little frustrated because everything he touched went in," Courier said.

"He was shanking balls and putting them in hard positions. . . . It's hard enough when he gets to so many balls in good position, but when he's going to be getting to balls late and hitting them off his frame and those go in, it's pretty tough."

Chang broke Courier to go up 4-3 in the second set, but the crowd behind him — everyone clearly wanted to see a third set — Courier broke back to even the score at 4-4.

But that was it for the evening, as Chang closed out the last two games, both at love.

"I just never really got going," Courier said. "It was kind of a seesaw night."