If the Washington Bullets perform as well tonight in Boston (WDCA-TV-20 at 7:30) as they did in last night's 127-98 rout of Detroit, the players believe they can beat the Celtics for the first time this season.

"If we play the way we did tonight, we'll beat Boston," Spencer Haywood said after scoring 21 points to lead nine Bullets in double figures. "We're on a good roll now."

By making 70 percent of their shots in the first half, the Bullets went ahead by 30 points and coasted to their third straight victory and ninth in their last 12 games, before 8,671 at Captial Centre.

Their biggest victory margin of the season (29 points) boosted the Bullets' record to 37-34, the first time they've been three games over .500 since aa seven-game winning streak raised their record to 22-19 on Jan. 26. Also, they're 1 1/2 games ahead of fifth-place New Jersey.

"This was a great night to have a blowout," Kevin Grevey said. "If we were pushed to the limit, it might have taken something out of our effort at Boston. This way, nobody had to play too many minutes and our confidence is up. There's no reson why we can't beat the Celtics if we play defense like we did tonight.

"The Celtics are deeper than Detroit, but they're not any better running team. Our defense just took that away and that's what we've got to do in Boston. You don't always know if you're going to hit your shots, but defense is one thing that can be consistent."

Defense? Coach Gene Shue talks so much about defense that even when the Bullets make 62 percent of their shots (54 of 87) and come within a basket of their season's highest score, the palyers still talk about defense.

"Our defense generates of the offense," Haywood explained. "When you play defense the way we did, the other team puts out so much effort to score, they don't have much left when they have to guard us."

Rick Mahorn again anchored the defense, blocking six shots and leading the team with nine rebounds, Detroit, which had won seven of its last nine games, made only 37 pecent of its shots in the first half and never got its running game going.

"Our defense is the reason we shot so well," Grevey said. "We got a lot of layups which were created by trunovers (the Pistons committed 22, leading to 25 points by the Bullets). When we forced them to take bad shots, it enabled us to get our running game going."

Frank Johnson, in one of his best all-round performances recently, led the Bullets' fast break with 12 assists and 10 points. When John Lucas relieved him, there was no let-down. The former Maryland star made five of six shots and had nine assists.

"That's the best we've played in a long time," Johnson said. "That's the type of flow I like to get the team into. We got a lot of guys involved. We got a big lead early, but we kept up our intensity. That's something we didn't do the last time Boston was here."

The Bullets led by 16 against the Celtics March 16 but lost, 98-97, in overtime. They haven't won at Boston Garden since March 9, 1980 and have lost nine straight at Capital Centre over three seasons.

"If we play this well, hell yes, we'll beat the Celtics," Shue said. "We've got a tough week with games at Boston, New Jersey and Atlanta, abut we couldn't be going on the road with a better attitude. Tonight was the best basketball I've seen since I've been here."

Haywood scored 12 points in the first quarter, leading a run of 14 straight points that put the Bullets in front, 34-14. Jeff Ruland came in and got 10 points in the second period when the Bullets scored 12 successive points to increase their advantage to 60-30 three minutes before intermission.

Quickly dispelling any doubt that the first half was a fluke, the Bullets made their first three shots of the third quarter and breezed to their sixth victory in their last seven home games.