Dwyane Wade dished off an assist on Haslem's game-winner, part of a performance that saw him lead all scorers with 30 points, while Quentin Richardson, Michael Beasley and Carlos Arroyo added 15 apiece in the win.
The Heat, which began the night tied for fifth place in the Eastern Conference, won their eighth straight road contest and 11th out of 12 overall.
Jason Kapono pumped in 24 points and Jodie Meeks contributed 21 off the bench for Philadelphia, which lost its seventh game in eight contests.
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UPI Sports Results for September 19, 2014