With both teams needing victories to make a run at the playoffs, Alex Tanguay scored for the Flames 4:27 into the third period to create a 2-2 tie. Overtime was looming and both sides appeared set to pick up at least one point when Getzlaf fired a slap shot past backup goaltender Leland Irving.
Anaheim reached 66 points for the season, three behind Calgary but seven behind San Jose and Dallas for the final playoff position.
The Ducks took a 2-1 advantage through two periods on a goal from Corey Perry, his 31st of the season.
Irving stopped 35-of-38 shots. Jonas Hiller made 27 saves in the win.