Game 2 of the best-of-7 series is in Anaheim on Saturday (8:30 p.m. MT; CBC, SN960).
"I think we were antsy and the energy and everything was going in the right direction but this was the first time for a lot of guys they've been in, or the first time in a few years. Guys were excited," forward Kris Versteeg said. "Those things will happen. They fought a hard game.
"But in the end we were still (in) there to win. We're going to bring our best."
Sean Monahan and Sam Bennett scored, and Brian Elliott made 38 saves for the Flames, who have lost 22 regular-season games and six playoff games at Honda Center since winning 5-2 on April 25, 2006 in Game 3 of the Western Conference Quarterfinals.
Rickard Rakell and Jakob Silfverberg also scored for the Ducks.
Bennett gave the Flames a 2-1 lead at 9:46 of the second period when he tipped Versteeg's no-look backhand pass by Gibson, but the Ducks struck twice in just under four minutes to take a 3-2 lead.
Getzlaf was stopped by Elliott after he was sprung on a 3-on-0 by Kevin Bieksa, but Rakell scored on the rebound at 13:53 to tie the game 2-2, and Silfverberg stepped off the boards on a powerplay and shot under Elliott's arm at 17:47 to make it 3-2.