Pierce scored 27 points, Garnett added 24 and Rajon Rondo had18 to go with 15 assists as the Celtics notched their third straight victory.
Boston led by as many as 18 points early in the game and held off a late Heat charge to win for the 18th time in 25 contests since the all-star break.
The Celtics also bested Miami 91-72 in an April 1 game.
Miami, meanwhile, fell to 1-2 on its current five-game homestand.
Boston schools pull out free condoms over wrapping complaints
NBC reportedly holds celebs hostage to Jimmy Fallon's show