Iguodala's dunk off a Ty Lawson air ball in the final minute turned back a late Warriors rally that saw Golden State whittle a 19-point deficit down to five with 2:16 to go.
Lawson finished with 19 points and 10 rebounds while Wilson Chandler pumped in five 3-pointers en route to 19 points for Denver, which still trails their Western Conference quarterfinal series 3-2.
Harrison Barnes (23 points, nine rebounds), Jarrett Jack (20, six, five assists) and Klay Thompson (19, six boards) led Golden State, which will have another chance to advance at home in Thursday's Game 6.
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