There are some things the surprising Washington Bullets just can't seem to do, and one of them is beat the Boston Celtics.

Although they slowed the NBA champions, although they played the game at their pace and although they played good defense, the Bullets lost to the Celtics tonight for the sixth straight time, 119-109.

Larry Bird was the difference. Still playing as a substitute, the all-star forward made 15 of 20 shots and scored 35 points to lead his team to its 31st victory in 37 games before the usual sellout crowd of 15,320 at Boston Garden.

"Although we were always pretty close, the Celtics had complete control," Coach Gene Shue said after the Bullets' four-game winning streak was ended. "They are an up-tempo team and we can't win playing that way."

Aside from Bird's excellent shooting, the Bullets seemed to have an answer for the Celtics' strengths.

Jeff Ruland made 10 of 14 shots and seven of eight free throws for 27 points and got 11 rebounds to offset a 21-point, 14-rebound effort by Robert Parish.

Kevin Grevey sank nine of 14 shots and scored 21 points to almost match the 23 points of the Celtics' starting guards. Greg Ballard outscored his man, Cedric Maxwell, 19-7, and Spencer Haywood had an 18-14 edge on Kevin McHale.

But nobody, of course, could match Bird. The three-year professional, playing his 11th straight game as a reserve, came in with 5:59 left in the first quarter and the score tied at 12. He made his first five shots. With the score 22-all, he sank a jumper in the lane, then a 17-footer from the base line to give the Celtics a 26-22 lead at the end of the quarter.

"He's always coming off a screen, and when he comes off he's ready to shoot," Shue said. "The only way to play him is to crowd him and force him left, but, obviously, that's easier said than done. You have to be on top of him when he catches the ball."

With Haywood getting 10 points and Ruland six, the Bullets caught up at 36-36 and kept pace until midway through the second period. Then another supersub, Nate Archibald, quickly scored five points and the Celtics ran off nine straight to take a 50-40 lead.

After making 13 of 18 shots in the first quarter, the Celtics finished the half shooting 64 percent and holding a 59-50 lead.

"How can you make a run at somebody when they're shooting that well?" asked Grevey. "We kept them from getting their break going. I thought we controlled them pretty well, but they just shoot so well."

After Frank Johnson, who had eight points, made two jumpers, the Bullets had closed within 65-60 four minutes into the third quarter. The Celtics then scored 10 of the next 12 points to turn back that threat.

"The Bullets are playing good basketball," Boston Coach Bill Fitch said. "We had to be on top of our game to beat them. I was very concerned. We lost the last one, then if we lost this one, we had to go on the road. I didn't want that."

Despite making 11 of 19 shots in the third quarter, the Celtics couldn't shake the Bullets, who were within eight, 86-78, after Rick Mahorn's leaner in the lane early in the fourth period.

Ruland and Haywood each scored twice and the Bullets still were a threat, 96-88, at the seven-minute mark.

The play that probably finished the Bullets' bid started when McHale blocked Don Collins' driving layup and whipped the ball downcourt to Parish for a three-point play that brought a cheering crowd to its feet and gave the Celtics a 101-88 lead with 6:51 remaining.

Grevey kept it from being a runaway with 10 points in the last five minutes, but couldn't prevent the Celtics from winning their 11th in 12 games against the Bullets the last two seasons.

"After they lost to Philadelphia, I knew they'd be ready for us," Grevey said. "They're the best team in basketball and we've played them a lot of close games, but they always find a way to win. That's why they're champions."

Bird said he was pleased with his shooting, but didn't feel his passing and rebounding (nine) were up to his usual high standards.

"I'm still adjusting to coming off the bench," he said. "The only disadvantage is that it takes me a couple of minutes to get into the flow of the game. I've got to make myself create something right away, because when I'm put in, we usually need some offense.

"It really doesn't matter about starting, except I'm not playing as many minutes (33) at home."

Nets 103, Cavaliers 87: Reserve guard Darwin Cook scored 19 of his 23 points in the last half as host New Jersey beat Cleveland.

Cook scored 13 fourth-quarter points and Len Elmore had nine in the period to finish with 18.

76ers 99, Bulls 98: Julius Erving scored 32 points and made two free throws with eight seconds left to lead Philadelphia over Chicago in the Spectrum.

The score was tied at 95 with 2:48 left, but Erving, who scored 18 points in the third period, made a layup with 2:41 left. The Bulls' Ronnie Lester made one foul shot but missed the second with 1:09 left and Erving's two free throws offset a layup by Dwight Jones at the buzzer.

Pacers 108, Pistons 106: Indiana's Billy Knight made a 20-foot jumper from the corner with three seconds remaining to beat Detroit in Bloomington, Ind.

It was only the third field goal of the game for Knight, who was inserted into the lineup during a timeout with six seconds left.

Detroit's John Long put up an 18-foot shot at the buzzer that bounced off the back of the rim.

Kings 116, SuperSonics 109: Mike Woodson's 28 points helped Kansas City to its seventh road victory of the year.

Seattle Coach Lenny Wilkens was assessed two technical fouls and ejected with four minutes left. Ernie Grunfield made both of the free throws to put the Kings up, 106-97.

Nuggets 120, Mavericks 119: T.R. Dunn's free throw with 1:01 remaining gave Denver a six-point lead in Dallas and the Nuggets survived a rally in the final seconds to win their 11th straight.

Rookie Mark Aguirre, who had 30 points, made a shot with 46 seconds to go and a three-point goal with 16 seconds left to cut the lead to one. Then the Nuggets' Glen Gondrezick missed two free throws with eight seconds remaining. Jim Spanarkel missed a jump shot with three seconds left and rookie Jay Vincent, who had 31 points, got the rebound, only to miss a layup.

Suns 127, Clippers 106: Walter Davis made 12 of 15 shots for 24 points in 20 minutes and Phoenix, with its best shooting this season, 64 percent, defeated visiting San Diego.