The Washington Bullets stayed with the Boston Celtics for 3 1/2 quarters tonight before fading and losing to the defending National Basketball Association champions, 113-100.

"They're the world champs and they find ways to win," Kevin Grevey of the Bullets said. "We played as well as we can. We would have beaten 20 other teams tonight, but we happened to be playing the best."

The sellout Boston Garden crowd of 15,320 had plenty to cheer about even before the game, when it was announced that the Celtics had signed Danny Ainge to a multiyear contract. Ainge is expected to make his debut with the Celtics at home Dec. 9 against the New Jersey Nets.

Seated with Celtic owner Harry Mangurian and General Manager Red Auerbach, Ainge watched attentively as the Celtics failed to pull away from the Bullets until the end. The Celtics appeared ready to blow the game open three times, but didn't. When the Celtics made their big surge in the final six minutes, however, the tired Bullets couldn't keep up. They lost to Boston for the third straight time this season.

The Bullets trailed only 93-91 with 6:28 remaining after Greg Ballard made three free throws, one of them after a technical foul on Boston's Cedric Maxwell.

The Celtics outscored the Bullets, 11-2, over the next 2 1/2 minutes, though, to take a 104-93 lead with three minutes left.

Maxwell started the spurt with two foul shots after a loose ball foul on Rick Mahorn. He also scored on a fast break basket.

Reserve guard Terry Duerod had a season-high 12 points in only eight minutes and he had two long baskets in the 11-2 spurt. In jeopardy of being cut once Ainge is ready to play, Duerod scored eight points in the second quarter when the other Celtics were having trouble finding the basket.

Coach Bill Fitch of the Celtics said Duerod "gave us the spark we needed to get us over the hump; he deserved the game ball."

Larry Bird's 24 points led six Celtics in double scoring figures. Bird had 14 rebounds, four assists and two steals, but committed an uncharacteristic eight turnovers.

Mahorn and Frank Johnson led the Bullets with 17 points apiece.

In that stretch when the Celtics pulled away, the Bullets missed six of seven shots, had two others blocked and committed a turnover. Their shot selection was questionable, at best.

"When we make a mistake, it has a lot more effect on us than it does on a team like the Celtics," Shue said. "They can overcome them. We can't."

The addition of Ainge made the outcome of the game somewhat anticlimactic for the Celtics and their fans.

"I'm not complaining," Fitch said. "I like what they've given me."

Ainge is believed to have signed for three years for between $400,000 and $500,000 a year. The signing came after nearly six months of negotiating with the Toronto Blue Jays baseball team, which held the rights to Ainge.

The Blue Jays were originally seeking $1 million from the Celtics to let Ainge out of his baseball contract, which had two years left to run, but they reportedly settled for about $500,000 after meeting most of the day with the Celtics.

Ainge, 6 feet 5, was an all-America at Brigham Young and one of Boston's two second-round draft choices. He was the 31st player selected overall.

Ainge had signed a baseball contract with the Blue Jays while still at BYU, but after batting only .187 as a third baseman this season, decided he wanted to switch to basketball, something his Toronto contract forbade him to do.

The Blue Jays balked at releasing him and the months of negotiations followed.

"I thought I was a better baseball player when I signed that contract, but I think I'm a better basketball player now," said Ainge.

"I always wanted to be a Celtic."

Tracy Jackson, from Notre Dame and Paint Branch High School, is also in jeopardy of being cut once Ainge actually joins the Celtics.

It seems like only a matter of time before he and Duerod both go, however, as M.L. Carr, on the injured list all season with a hairline fracture in his left leg, is about ready to be activated.

The Bullets will play the Indiana Pacers tonight at Capital Centre.