Los Angeles  - The short-handed Boston Celtics rode the hot hand of Paul Pierce to shoot them over the finish line.

Pierce poured in 21 of his 36 points in the fourth quarter and overtime, and the Celtics beat the Miami Heat 112-108 on Wednesday night to clinch their second straight Atlantic Division title.

"With bodies going down left and right, we just needed a win so desperately right now to get our spirits back up," Pierce said. "We needed an extra boost in scoring, so I just wanted to step up my game while the guys were out."

The reigning NBA Champion Celtics were without Kevin Garnett (right knee strain) for the 13th straight game, and lost fellow-All- Star Ray Allen to a hyper-extended elbow on Tuesday night.

Additionally, top reserves Leon Powe (left knee sprain) Tony Allen (thumb) and Brian Scalabrine (concussion) were sidelined by injuries.

"We're going through a tough stretch with all the injuries, but we know the big picture," Celtics coach Doc Rivers said. "The only way you can put a puzzle together is with the box. We just don't have all our pieces together, but we know we're going to get them back."

The Heat was without the NBA's leading scorer Dwyane Wade, sitting out his first game of the season with a right hip flexor.

"It came down to Paul and Wade," Rivers said. "And they didn't have Wade."

Rajon Rondo had 27 points while Eddie House scored 16 off the bench for Boston (51-18) which stayed one-half game ahead of Orlando for the second seed in the Eastern Conference playoff chase.

"Paul's our go-to guy, we kept going to him," Rondo said. "He was feeling it all night long. He came up big in the fourth quarter, and hit a big three (pointer) to start the overtime. That's how we got the win."

Pierce erupted for 16 fourth-quarter points, including the go- ahead jumper, putting the Celtics ahead, 100-99. However, Mario Chalmers' free throw squared it, and the game went into overtime when Pierce's game-winning jumper rimmed out at the buzzer.

The Celtics opened the extra session on an 8-0 run. House and Pierce buried three-pointers followed by Rondo's runner to make it 108-100 at the 2:54 mark. Chalmers' three drew the Heat within six. However, after House split two free throws, Pierce made both of his to wrap up the win.

Michael Beasley scored 21 points and Chalmers finished with 19 for Miami (36-31) which despite the loss remains fifth in the East playoff scramble. (dpa)