Ray Allen scored 12 of his 24 points in the third quarter and made 10 of his first 11 shots, leading the Boston Celtics to an 87-86 victory over the Los Angeles Lakers on Thursday night.

It was the defending NBA champions' first loss in five games since Kobe Bryant went down with a sprained left ankle.

Kendrick Perkins had 13 points and 14 rebounds, Kevin Garnett had 13 points and eight boards and Rajon Rondo added 14 points and 11 assists for the Celtics, who were busy before gametime. They acquired guard Nate Robinson and Marcus Landry from the New York Knicks in exchange for Eddie House, J.R. Giddens, Bill Walker and a future conditional second-round pick.

Pau Gasol scored 22 points, and Lamar Odom had 13 points and 14 rebounds for Los Angeles.

Bryant, the league's fourth-leading scorer, remained in the trainer's room getting treatment on his sprained left ankle while his teammates rallied against a defense that came in allowing a league-low 93.7 points per game.

The Lakers had won the previous three meetings with the Celtics after losing the 2008 finals to them in six games. On Jan. 13, they beat Boston 90-89 on the parquet floor, after Bryant hit a jumper with 7.3 seconds left to give the Lakers their only lead of the second half and Allen missed 3-point shot at the final horn.

The Lakers went 4 minutes, 48 seconds without a basket until Odom's layup with 2:26 to play. Garnett missed a 21-footer with 51 seconds left, but the Lakers lost possession on a turnover by Gasol. The Lakers got the ball back and Odom missed a driving layup with 2.2 seconds to go.

The groans from the sellout crowd turned to audible sighs of relief when everyone realized the Lakers had called a time out just before Odom made his move to the basket. But the ensuing inbounds pass from Ron Artest to Derek Fisher resulted in a missed 21-footer by Fisher at the buzzer with Allen's hand in his face.

The Celtics were leading 66-55 when Garnett picked up his fourth foul and went to the bench with 8:27 left in the third quarter. He was replaced by Rasheed Wallace, who received a technical foul from referee Bob Delaney with 3:10 left in the period for shoving Gasol as the two power forwards jockeyed for position.

Garnett didn't return to the floor until 7:53 remained in the game. By then, the Lakers were eight points into a 13-0 run triggered by two layups by Sasha Vujacic and capped by Andrew Bynum's 20-footer. The basket gave Los Angeles an 84-80 lead with 7:14 to play, but Perkins' layup put Boston back in front to stay with 4:24 remaining.

The Celtics shot 55 percent in the first half to build a 53-48 margin. The Lakers took their first lead of the game, 34-32, when Odom sank a pair of free throws with 9:39 left in the second quarter.

Boston responded with a 15-2 run capped by Allen's fastbreak dunk with 5:09 left in the second quarter, after Rondo stole the ball from Gasol. Rondo received a technical foul for taunting the Lakers after Allen's basket, and Fisher converted the free throw.

Shannon Brown beat the first-quarter buzzer with a 3-pointer that trimmed Boston's lead to 29-27. It was his fourth straight start in place of Bryant, after setting career highs with 27 points and 10 rebounds in Tuesday's 104-94 win over Golden State.

NOTES: Wallace's technical foul was his 13th this season. Three more will get him an automatic one-game suspension. The NBA recently rescinded two technical fouls he already had been assessed. ... The last time the Lakers hosted Boston, on Christmas Day 2008, they snapped the Celtics' franchise-record 19-game winning streak and gave Phil Jackson his 1,000th victory as an NBA head coach. ... Allen ended a three-game stretch for the Celtics in which no player scored more than 17 points. ... Garnett needs 16 rebounds to become the 20th player in NBA history with at least 20,000 ... Artest "posterized" Wallace with a thunderous dunk that reduced Boston's lead to 41-36 with 6:57 left in the half.

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