BOSTON, Massachusetts - Kevin Garnett scored 24 points to lead Boston over Miami 100-98 in two overtimes on Sunday but the joy of ending a six-game NBA losing skid was dimmed by the loss of Rajon Rondo for the season.
The Celtics announced during the game that star point guard Rondo, voted by fans as an Eastern Conference starter in the NBA All-Star Game, will miss the remainder of the season with a torn right knee ligament.
"We've just to rally around each other," Celtics forward Paul Pierce said. "I feel for him. He was having such a great season. I'm disappointed for him."
Rondo suffered the injury in Boston's double-overtime loss at Atlanta and was dropped from the line-up to face Miami at the last minute and sent to a Boston hospital for medical tests that revealed the extent of the injury.
Rondo, who has averaged a NBA-best 11.1 assists plus 13.7 points over 38 games this season, will have surgery at a date yet to be determined, the team said.
The Celtics, who improved to 21-23, were already reeling from their losing skid but battled the Eastern Conference-leading Heat to the finish repeatedly before finally claiming victory.
"This team has a lot of heart and pride," Pierce said. "Even though we lost six in a row, we felt like we were beating ourselves. It was about grit and grinding and struggling and finding a way to do it without Rondo."
Pierce produced his seventh career triple double, but his first since 2010, with 17 points, 13 rebounds and 10 assists. Jason Terry scored 13 points and Jeff Green added 11 off Boston's bench. Garnett also grabbed 11 rebounds.
LeBron James scored 34 points and grabbed 16 rebounds while Chris Bosh added 16 points and 16 rebounds and Dwyane Wade contributed 17 points.
Former Celtics star Ray Allen, in his first game back in Boston since joining the Heat, had 21 points off the bench.
Boston led 85-81 late in regulation time before Allen hit a three-pointer, trimming the Celtics' lead to a point.
Terry sank a pair of free throws for Boston after being fouled by Wade to rebuild a three-point edge. Allen missed a repeat effort from the corner but James followed with a three-pointer from outside the top of the arc to equalise at 87-87.
In the first overtime, James scored on a driving layup and dropped in a rebound shot to put the Heat ahead 93-89, only to have Garnett pull Boston level with a layup and baseline jumper to make it 93-93 to force another extra five-minute period.