The Portland Trail Blazers ruined what was supposed to be a festive occasion for Dick Motta last night by trouncing Washington with the kind of overpowering team basketball the Bullet coach loves so dearly.

Good for Motta, he didn't see much of it.

At times in the 132-104 rout the Trail Blazers appeared to be toying with the defending NBA champions, who were seeking Motta's 500th league win. It was the second-worst loss in Capital Centre ever by the Bullets.

Motta said he could tell his club didn't have it in the early minutes of the first quarter. He had to make a quick assessment, hecause he was ejected with 2:58 left in that period after picking up his second technical.

His players and the 15,708 who showed up to set a season club attendance record weren't so lucky. They stayed around and witnessed the debacle produced by an opponent supposedly crippled by the season-long loss of center Bill Walton.

"I thought for a while No 33 (Walton) was out there," said Motta, referring to Portland's impressive offensive execution and the scoring of center Tom Owens, who has played like an All-Pro this year against Washington.

Owens, who has averaged almost 25 points in four games against Washington, headed a group of outstanding performers. The Trail Blazers registered a staggering 43 assists, 30 layups and 60 percent shooting. They even looked efficient during garbage time, which is quite an accomplishment in the NBA.

"We might not have played better than this," said an admiring Jack Ramsay, who has turned in a topnotch coaching job with the injuryplagued Blazers. "I think we caught the Bullets a little flat for this one. We have to play hard; we have won 43 games and we still don't have a playoff berth yet."

There may not be a team in the league playing better than Portland right now. The Trail Blazers have won seven of their last eight games and seven of their last nine road tests as they strive to earn a Western Conference playoff spot.

They have overcome as many injuries as the Bullets and now Ramsay finally thinks he has everyone-setting aside Walton-healthy and ready to play together, except guard Lionel Hollins who has a sore knee.

"The key has been since we started (rookie) Mychal Thompson at small forward," said Ramsay. "We've lost only maybe three since then. He can play that position (at 6 feet 10) because he is such a good defender."

With Thompson, 6-9 Maurice Lucas and 6-10 Owens, the Blazers have a huge and mobile front line that even the Bullets' talented front court failed to handle.

Through three quarters, when Portland had a 99-68 lead, Owens had his 30 points on 14-of-20 shooting. Thompson had 20 points on 10-of-18 marksmanship and Lucas added 16 on eight-of-15 accuracy. And what these big men didn't score, the Blazer guards contributed off layups set up by breathtaking cuts to the basket.

"Washington was sort of coasting but it's that time of year," said Thompson, who began the season as a starter when Lucas was out with a hand injury. "This game meant more to us than to them. Once we got ahead, they gave up. At least that's how it looked to me,"

Even the unexpected return of guard Kevin Grevey, who had been out almost two weeks with the latest in a series of hamstring pulls, couldn't bolster the Bullets.

Grevey had contemplated sitting out the rest of the regular season but told Motta before the game his leg felt so good he wanted to play. He got in for 14 minutes and scored four points.

"We had a long talk," Motta said. "I told him to use common sense and make a mature decision. It's important for him to play now but we have to look at the long range too. But he said no one knows his body as well as he does and he had the doctor's clearance to play."

Portland took control early in the second period. Leading, 37-34, the Trail Blazers ripped off six straight points and, moments later, another string of seven for a 15-point bulge. Two three-point plays by Elvin Hayes, who finished with 18, trimmed the margin to 11 at half.

But Ramsay's crew came out cooking in the third.

With Owens tossing in 16 points, the Blazers outran and outshot the Bullets and had some fans in the Centre booing and heading for the aisles before the quarter ended. At one point, Portland outscored the home club, 26-6, and hit its final nine shots of the period.

The Bullets have lost their last two home games and three of their last five contests to foil their bid to wrap up the league's best record. They lead Seattle by 2 1/2 games with six to go.