MIAMI - LeBron James scored 34 points and grabbed 10 rebounds, Dwyane Wade scored 23 and the Miami Heat pulled off the biggest playoff comeback in franchise history to beat the Boston Celtics 115-111 in overtime on Wednesday night.

Mario Chalmers scored 22 for the Heat, who took a 2-0 lead in the Eastern Conference finals despite an unbelievable night by Rajon Rondo. The Celtics guard played all 53 minutes and scored 44 points, dished out 10 assists and grabbed eight rebounds.

Paul Pierce scored 21 points, Kevin Garnett added 18 and Ray Allen 13 for Boston.

Game 3 is Friday in Boston.