Danny Green had seven of his nine three-pointers from a 27-point total and Gary Neal landed six from 10 from deep from his own haul of 24.
The Spurs, beaten by 19 points in Game Two as the Heat tied things up at 1-1, won by an emphatic 36-point margin as Tim Duncan added 12 points and 14 rebounds.
LeBron James, a four-time most valuable player, had a disappointing night as he only picked up 15 points. San Antonio will again be the host today when the series reaches Game Four.
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