After losing a four-point lead in the final three minutes, then scoring only two points in the last two minutes of overtime, the Bullets were beaten by Boston, 103-99, yesterday at Capital Centre despite another magnificent effort.

Spencer Haywood missed a 12-foot shot at the buzzer in regulation that would have given the Bullets a victory. Instead, Kevin McHale scored six points in overtime and had a crucial block of a shot by Kevin Grevey, and Washington now trails, 3-1, in this best-of-seven Eastern Conference semifinal against the defending NBA champions. The fifth game is set for Wednesday in Boston at 7:30 p.m.

"We played as well as we could play," Coach Gene Shue said, summing up the Bullets' problem in this series: no matter how well they play, they lack the strength and depth to beat the Celtics consistently.

Victory was well within the Bullets' grasp after they built a 62-52 lead midway through the third quarter, but on their next three possessions, Don Collins missed two layups and Greg Ballard one. Instead of a commanding 16-point lead, the Bullets' advantage dwindled to 73-69 by the end of the period.

"That was a very important stretch," Shue conceded. "They were tough shots, but we could have made them."

Another big reason for the Celtics' come-from-behind victory--their 11th straight at Capital Centre--was offensive rebounding. The Celtics got 19 and turned them into 20 points. The Bullets managed only 12, which were worth 15 points.

"Offensive rebounding was an enormous factor," Shue said. "We played great defense, then they would get a missed shot and put it back in. That's very discouraging."

Generally, the Bullets' demise was caused by those three missed layups, the Celtics' offensive rebounding and brilliant performances by Robert Parish (28 points, 15 rebounds and three blocked shots) and McHale (25 points, seven rebounds and five blocks). There were many key plays, and the Bullets had several opportunities to win this game.

Once the Celtics caught up, at 75-75, there were seven more ties in the fourth quarter.

With 38 seconds left, Rick Mahorn missed the second of two free throws, though the Bullets had a 91-89 lead. Ballard got the rebound of Mahorn's miss but fell and lost the ball to Cedric Maxwell. Following a timeout, Maxwell was fouled by Mahorn, and made two free throws to tie the game at 91 with 17 seconds left in regulation.

The Bullets then had an excellent chance to win and force a sixth game here next Friday night. During a timeout, Shue called a play for Haywood, his most productive scorer (28 points). Frank Johnson got the ball to Haywood with about six seconds left, but the veteran forward appeared rushed and his 12-footer from the left side hit between the back rim and the backboard and bounced away as regulation ended.

"I wanted to wait until there were three or four seconds left, but I waited a little too long," Haywood said. "I didn't have time to maneuver, but I should have put it in. I had time to do what was necessary. I tried to draw a foul and I got hit, but I didn't get the call."

Before Haywood's miss, which caused the enthusiastic crowd of 16,295 to groan, Jeff Ruland and Mahorn each had made only one of two free-throw opportunities. Their misses were offset by McHale, who missed two with 39 seconds to play.

In overtime, the Bullets nudged in front, 97-95, on Mahorn's short jumper with 2:06 remaining, but didn't score again until Frank Johnson made two free throws with six seconds left.

During that decisive stretch, Ballard made a bad pass, trying to lob the ball to Mahorn, then Mahorn tried to force a pass inside to Haywood. "If the opening's not there, you're not supposed to throw it," Shue said.

On the next possession, the Celtics' defense was very aggressive and neither Johnson nor Kevin Grevey could get free. Mahorn called for the ball, near the top of the foul circle, then shot a 17-footer that bounced off the rim.

"The shot clock was winding down," said Mahorn, who had shot from beyond his usual range. "They were playing good defense on our guards."

Johnson then fouled Nate Archibald in the back court and the Celtics' playmaker made both free throws to give Boston a 100-97 edge with 18 seconds left. During a timeout, Shue set up a three-point play for Grevey, who had made four of eight shots. Johnson, who made the three-point game-winner in Boston, has made only one outside shot since.

"I ran my man (Gerald Henderson) off a double pick," Grevey explained. "I had him beat, but as I was getting my feet together for the three-pointer, McHale came out of nowhere like he's done all series and blocked it. I tried to initiate contact and draw the foul.

"I thought I had an opening, but I knew they were ready for a three-point shot. It's only a 28 percent shot during the regular season and when a team like Boston is ready for it, it's not a very high percentage play."

When Larry Bird (10 points), grabbed the blocked shot, Grevey fouled him and the all-star forward made both free throws. The 102-97 score sent fans to the exits.

"We did everything we tried to do," Shue said. "We held them to 91 points for four quarters, Ballard did another sensational defensive job on Bird. There's not much we can do differently in Game 5."

The Bullets' biggest problem is containing Parish and McHale, who combined to score 53 points, make 23 of 38 shots, get 22 rebounds and block eight shots.