It was the third 3-pointer of the final period for Radmanovic and put the Hawks in front. Two free throws by Jerry Stackhouse with 6 seconds left clinched the victory.
The Hawks trailed by as many as 16 early in the second half before coming back for just their fifth victory in 14 games.
Josh Smith had 24 points and 19 rebounds for Atlanta, which survived 23 turnovers. Radmanovic scored all nine of his points in the fourth period.
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