Ryan Getzlaf returned after missing four games with back spasms and scored for the Ducks (34-37-10), and Ryan Miller made 25 saves for his 378th NHL win, moving him four ahead of John Vanbiesbrouck for the all-time lead among U.S.-born goalies.
Derek Ryan scored, Johnny Gaudreau had an assist for his 98th point of the season, and David Rittich made 29 saves for the Flames (50-24-7), who had won three in a row and nine of 12.
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Calgary clinched the No. 1 seed into the Stanley Cup Playoffs from the Western Conference for the first time since the 1989-90 season with a 5-3 win against the San Jose Sharks on Sunday.
The Flames rested several players, including forwards Sean Monahan and Elias Lindholm, and defenseman Mark Giordano. Monahan is second on the team with 82 points (34 goals, 48 assists), Lindholm is third with 78 points (27 goals, 51 assists) and Giordano is fifth on the team and second among NHL defensemen with 74 points (17 goals, 57 assists).
"A lot of ice time for some young guys and a lot of opportunity for some guys that they don't usually get it," Calgary coach Bill Peters said.