The Washington Bullets have been riding the crest of newly found confidence. Nevertheless, tonight they found themselves swept away by the Boston Celtics, a team long acquainted with confidence. The final score at Boston Garden was 116-97, but the Celtics seemed capable of setting whatever margin of victory they desired.

In breaking the Bullets' three-game winning streak, Boston (60-13) extended a number of its streaks. The victory was the Celtics' 10th in a row and 26th straight at home, one short of the NBA record set by the Minneapolis Lakers in 1949-50. Overall, the Celtics are 35-1 at home.

After taking a 35-20 first-quarter lead, Boston repeatedly allowed Washington to come within striking distance before pulling away. On 13 occasions, the Celtics had runs of four or more points. They were smallish bursts that grew impressive when viewed cumulatively.

"Not many teams are as loose as they are at the start of a game," said Bullets forward Dan Roundfield. "Once they get you down it just gets worse and worse and worse."

Indeed, while the definitive streak was an 18-8 run to open the fourth quarter, the game effectively was over much earlier. In the first 18 minutes of the game, the crowd of 14,890 (the Celtics' 255th consecutive home sellout) was treated to such sights as all-star forward Larry Bird diving headlong to save a loose ball, and center Bill Walton using a nifty reverse pivot move to dunk over the Bullets' Manute Bol.

Bird led Boston with 27 points but the tone of the game was set by Walton. Starting in place of Robert Parish, who was sidelined with a bad back, Walton finished with 20 points and tied Bird's total of 12 rebounds.

Thirteen of Walton's points came in the first period. By halftime, the Bullets, who were led by guard Jeff Malone's 18 points, had discovered another emotion -- frustration. On one play, Washington's Cliff Robinson accidently tipped the basketball through the hoop for the Celtics. A short time later, Bullets guard Leon Wood was called for an offensive foul before the ball could be inbounded. A little while after that, Kevin McKenna clubbed Boston's Jerry Sichting on a drive to the hoop but the shot still went in.

"Those guys are obviously in a different class than us right now," said Washington Coach Kevin Loughery. "They're just a terrific team. They play team defense as well as anybody in the NBA. K.C. Jones should get more credit for what he does."

Jones, who once coached the Bullets, continued a streak of his own and set an NBA record to boot. The victory gave him three consecutive 60-victory seasons, and he became the first coach to win 60 four times.

"I feel very fortunate to have learned from and been with many great people," said Jones, a mainstay of many of the Celtics' 15 championship teams under Coach Red Auerbach. "Red never bothered anyone until it was time to, and that was maybe once a month."

Of course, with players like Jones and Bill Russell, Auerbach probably had little occasion to be concerned with his team's play, which is similar to the position the present coach finds himself in.

"Their defense was really strong tonight. We just couldn't get close," said Robinson, referring to the Bullets' 39 percent shooting from the field. "We had some shots to get it down to seven or nine but we just couldn't do it."

The Bullets fell to 35-39 and into fourth place in the Atlantic Division behind New Jersey, a winner over Chicago tonight. They can move back into a tie with a victory over the Houston Rockets Saturday night at Capital Centre.