The Heat were behind 107-105 with 7.7 seconds remaining in the fourth quarter when Dwyane Wade fed a behind-the-back pass to Bosh, who set up and launched the game-winning shot, ending the game with 37 points.
Bosh connected on 15-of-26 shots from the field and drained a trio of 3-pointers in the fourth quarter for the Miami, which was playing without James (groin, ankle).
Wade scored 16 points, and Mario Chalmers supplied nine points, nine rebounds and nine assists.
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