Anaheim announced the deal Wednesday night after a 7-6 loss to Washington.
Mara had two points in 33 games this season with the Ducks, who signed him to a one-year, $750,000 contract shortly before training camp. He hadn't played since Jan. 18, missing eight straight games and 23 of 25 as a healthy scratch.
The Ducks reacquired defenseman Francois Beauchemin from Toronto last week, further decreasing Mara's chances of playing for Anaheim.
Mara played 48 games for the Canadiens last season before a season-ending shoulder injury. Anaheim was his sixth NHL team.
It's an incredible feeling just to see it go in and see the Joe go pretty crazy. Ever since the introduction there, I was kind of feeling the nerves, and to put that one home, I started to feel comfortable and I thought my play started to pick up.
— Nineteen-year-old Red Wings forward Dylan Larkin after scoring a goal in his NHL debut
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