Three plays later, Prater kicked the game-winner for the Broncos (2-4).
Tim Tebow made his first start of the season for Denver and guided them to a pair of touchdowns late in the fourth quarter, erasing a 14-point deficit and forcing an overtime.
Tebow (13-of-27, 161 yards) capped a 10-play, 55-yard desperation drive with a 3-yard scoring pass to Daniel Fellis to forge a 15-15 tie with 17 seconds left in regulation.
Moore, subbing for the injured Chad Henne, finished by going 22-of-33 through the air for 197 yards and a score for the winless Dolphins (0-6).
Notable deaths of 2014 [PHOTOS]