James Michael McAdoo scored 16 of his 20 points in the fourth quarter and the Warriors rallied to beat the Nuggets 104-101 on Thursday night for their fourth straight victory.
Golden State's Klay Thompson added 18 points in the first NBA exhibition game in Des Moines since 1997.
The Nuggets led by 13 heading into the fourth quarter. But The Warriors (4-0) retook the lead, 100-99, on Jason Kapono's 3-pointer with 1:47 left, and Harrison Barnes sealed it with a jumper with 6.8 seconds left.
Wilson Chandler and Timofey Mozgov each scored 18 points for Denver (1-4), which dropped its third straight game.
The game marked Barnes's return to his native Iowa. He finished with five points.