Iguodala's trey with 7.1 seconds remaining in the extra frame wiped out a 118-116 Bulls lead and the Nuggets hung on for their 12th straight win when Joakim Noah was called for offensive goaltending with 1.7 seconds left.
On the play, Marco Belinelli launched a jumper that appeared to be short of the rim and Noah deflected it through the hoop for an apparent game-winner.
The officials, however, overruled the basket after they determined via a video review that Noah touched the ball as it was in the cylinder.
Wilson Chandler finished with 35 points for the Nuggets.
Nate Robinson led Chicago with 34.
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