Boston led 46-43 at halftime and stretched that to 70-55 with 3:36 left in the third quarter. At that point, the Celtics had made 9 of their 10 shots in the period while the Magic had hit just 4 of 18.
Orlando scored the last six points of the third quarter, cutting the lead to 70-61, but the Celtics came right back with a 7-2 run to go ahead 77-63. They led by at least eight the rest of the way.
Paul Pierce added 18 points and Kevin Garnett had 16 for the Celtics, who improved to 23-4 at home. Dwight Howard had 28 points and 13 rebounds for the Magic, who lost for the fifth time in eight games.
Ray Allen made 2 of 4 3-pointers and moved within three of the NBA record of 2,560 made 3-pointers held by Reggie Miller. Allen can improve on his total of 2,557 at Charlotte on Monday night.
The Magic made just 3 of 24 shots from 3-point range after entering the game ranked ninth in the NBA with a 36.8 percentage. They've taken and made the most 3-pointers in the league. Overall, they took 30 more field goal attempts than the Celtics but made just two more.
Celtics backup guard Marquis Daniels was taken off the court on a stretcher after he hurt his back in a collision with Gilbert Arenas with 11:01 left in the second quarter. He was taken to New England Baptist Hospital for examination.
Daniels was hurt after he began driving to the basket from the right side of the lane and hit his head on Arenas' left shoulder. Daniels fell and lay motionless for a few minutes with his head facing down while surrounded by his coaches and teammates near their bench. Medical personnel put a neck brace on him and strapped him onto a stretcher. He gave a thumbs-up sign as he left to the cheers of the crowd.
Leading by three at halftime, Boston took control by scoring the first seven points of the third quarter, taking a 53-43 lead. Pierce began the spurt with a 15-footer, Garnett added a baseline jumper and Allen hit his second 3-pointer of the game.
Jason Richardson followed with a 3-pointer for the Magic before Rondo made two free throws and Pierce sank a layup for a 57-46 lead with 8:23 left in the quarter.
It was 65-55 before the Celtics ended the quarter with five straight points - a 3-pointer by Rondo and a layup by Garnett.
The Magic had raced to a 12-2 lead before the Celtics took their first lead 41-40 with 1:01 left in the half on two free throws by Garnett.
Boston's Glen Davis bruised his head and Orlando's Jameer Nelson was kicked in the ribs when they collided under the Magic's basket with 3:57 left in the first quarter. Both left the game but returned in the second quarter.
Notes: Orlando F Brandon Bass missed his third straight game with a sprained left ankle. ... Boston C Shaquille O'Neal missed his second straight game, and is expected to sit out at least one more, with a sore right leg. ... Orlando's Howard, Nelson and Earl Clark received technical fouls in the first half. The Celtics had none for the game. ... The teams also met in Boston on Super Bowl Sunday last year with Orlando winning 96-89.