Jerome Robbins, the choreographer, stood in the atrium reception room on top floor of the Kennedy Center receiving accolades for his work. The New York City Ballet had just finished performing, and it had gone well.

But there was just one problem with the second work, "Dances at a Gathering." The piano accompanist was literally sitting on the stage instead of in the orchestra pit.

"We usually don't have the piano on stage," said Robbins smiling calmly, twirling his wine glass in his hand. "It won't be there at the next performance."

In addition to the piano on stage, which didn't seem to interfere with the dancers, there was another problem with last night's performance. Mikhail Baryshnikov was not there to dance in it, because of a foot injury. But the guests who attended the ballet board supper afterwards still spoke approvingly of the performance.

"To tell you the truth I personally didn't miss him," said Heidi Swan of the National Endowment for the Arts, who praised the company highly "But I would think a majority of the people did."

They didn't show it. Instead they talked to the many dancers from the company who had come into the party. "Patricia McBride, one of the principals in a Gershwin number, was constantly complimented on her work.

"I always love doing the Gershwin numbers. It's a very stimulating thing to do. I can play around with it a lot," she said, clutching the arm of her husband, principal dancer Jean Pierre Bonnefous.

You could tell the dancers at the party last night. They were all thin and fashionably dressed. The women had pale skin color and dark eye makeup. And they all sat together, either at a table in the atrium or scrunched up on a leather bench in the center of the room.

"I didn't watch it," said Stephanie Saland, 25, who doesn't dance in the ballet until Friday night. "I was backstage practicing at the bar."

The nondancers at the party wore business suits and talked to the dancers with awe in their eyes. They also had the late hour on their minds.

"I'm gonna leave," said Rep. Sidney Yates (D-Ill.), giving Robbins a hearty handshake. "I've got to go to work in the morning. I'll leave this for you fellas."

"What do you think I'm doing tomorrow?" Robbins responded with a grin. "I'm going to have rehearsal all day tomorrow.You think I'm going to be loafing?"