The Detroit Pistons knew the Boston Celtics, winners of an NBA-record 16 titles, had the will and the skill to rally from an 18-point deficit.

The Pistons also knew, having won the last two championships, that they wouldn't come unraveled when the Celtics came back.A 79-61 cushion shriveled to nothing when Larry Bird's 18-footer tied the score at 100 with 3:40 left.

But Bill Laimbeer's long-range bombing carried the Pistons to a 116-111 victory Wednesday night, giving them a 3-2 lead in the best-of-7 Eastern Conference semifinal. Detroit is a win away from a third straight conference final matchup with the Chicago Bulls, who defeated Philadelphia in five games.

Portland plays host to the Los Angeles Lakers in the opener of the Western Conference finals on Saturday.

In a series in which the homecourt hasn't been an advantage, Detroit can clinch at home Friday night. Boston, 1-1 on the road and 1-2 at home in the series, would be home for a seventh game on Sunday, if necessary.

"It's not grim in here," guard Dee Brown said in Boston's locker room. "We just have to go back there and (win) again."

"I like Boston, but I sure don't want to come back here for Game 7," Detroit Coach Chuck Daly said. "Only on vacation."

Wednesday night's game was hardly that for the Pistons, who couldn't relax until the final seconds even though they never trailed in the last period.

"They made a tremendous run in the fourth quarter," Detroit's James Edwards said. "I knew they would."

And the Pistons, with all their big-game experience, were ready for it.

"A few years ago, we probably would have lost our poise in a situation like that," Detroit's Vinnie Johnson said, "but we kept executing offensively and defensively."

The deadliest executioner was Laimbeer.

He had made just 16 of 47 shots, a 34 percent average, in the first four games. But on Wednesday night, he was 8-for-14 and made his last three shots.

His jumper from the top of the key gave Detroit a 102-100 lead with 3:25 to go. His shot from the corner made it 104-102 with 2:11 left. And his 20-footer from the corner, just two seconds after a Pistons timeout, gave them the lead for good, 108-106 with 39 seconds remaining.

"There were only six seconds on the shot clock. I had to take the first shot I got," he said of the go-ahead hoop. "Making shots like that is my job."

It's also the job of Detroit guards Joe Dumars and Johnson. But they hadn't been doing it. In the first four games, Dumars made 37 percent of his shots and Johnson only 31.6.

But in Game 5, Dumars was 9-for-17 from the field and 13-for-13 from the foul line for a game-high 32 points. Johnson was 11-for-19 for 24 points. Laimbeer also had 24.

Isiah Thomas, who missed Games 2 and 4 with a sprained foot, was scoreless in 15 minutes.

"Vinnie and I hit a few shots and stretched out their defense," Dumars said.

"We knew, sooner or later, their guards would get hot," Boston coach Chris Ford said. "Detroit shot the ball real well."

The Pistons percentage, 38.7 in the first four games, was 50.6 as they outshot Boston for the first time in the series.

The Celtics did get 30 points from Reggie Lewis and 19 from Brown. They also shook off their rebounding woes in the series, beating Detroit 43-33 off the boards.

And they overcome numerous adversities to fight back.

Bird, hampered by a bad back, was ineffective for the first three quarters. Center Robert Parish turned his ankle three times in the first half and sat out the second. His status for Game 6 was unknown.

And Detroit used a 12-2 run at the end of the first half to go ahead 65-55 and a 10-2 spurt at the start of the second to take a 75-57 lead with 8:48 left in the third quarter.

The Pistons still led 98-88 before a 12-2 Boston run tied the game.

"We played ourselves into a big hole," Boston's Kevin McHale said. "We battled hard, but it's not any good unless you win."

Bird had 10 of his 16 points in the final period but missed his only two shots after he tied the score 100-100. He missed a jumper with 3:09 to go that would have evened the game at 102. Bird missed a 3-point shot with 24 seconds remaining.