Vince Carter scored a team-high 20 points and Dwight Howard had 16 and 13 rebounds to lead the charge for the Magic, who enjoyed a 19-0 run in the third to turn a nine-point deficit into a 70-60 lead behind a barrage of three-pointers.
Boston held a 51-40 lead at halftime but faltered to lose their first in four games.
Rajon Rondo paced the Celtics with 17 points, nine assists and eight rebounds. Paul Pierce returned from a two-game absence due to an ankle injury to finish with 13 points.
In the fourth and final meeting between the teams that faced in last year’s postseason — a best-of-seven series won by the Magic 4-3 — Orlando prevailed against Boston for the third time this season.
The Magic (34-17) fell behind in the second quarter and had to hold on in the fourth when the Celtics trimmed a 17-point deficit to just five with 43 seconds left.
“Five more minutes and they probably would have got the win,” Howard told reporters after fighting early foul trouble. “We have to play hard for 48 minutes and we can’t give up big leads like we did today. Thankfully, we were able to grind out the win.” Point guard Jameer Nelson recorded 15 points and Rashard Lewis added 14 for Orlando.
Boston brought back key reserve Marquis Daniels who had missed 29 games due to thumb surgery. Daniels had eight points and Ray Allen put up 14.
The Celtics (32-17) continued their trend of losing to the league’s top contenders, including a recent loss to the Los Angeles Lakers and four defeats to the Atlanta Hawks.
“(Orlando) knocked us out of the playoffs last year,” Boston coach Doc Rivers said. “Orlando’s better than us right now. Atlanta’s better than us right now. L.A. (Lakers are) better than us right now.”