The 24-year-old forward, who was a restricted free agent, avoided a salary arbitration hearing scheduled for Oct. 20.
"It's really exciting," Mangiapane told the Flames website. "I love the team; I love the city. I love everything about Calgary, so I couldn't be happier to be back for another two years."
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Mangiapane had NHL career highs in goals (17), assists (15) and points (32) in 68 games with the Flames last season and scored five points (two goals, three assists) in 10 Stanley Cup Playoff games.
Selected by Calgary in the sixth round (No. 166) of the 2015 NHL Draft, Mangiapane has scored 45 points (25 goals, 20 assists) in 122 regular-season games and six points (three goals, three assists) in 15 playoff games.
"I still think there's a lot of room for me to grow, and a lot more for me to show, offensively," he said. "I'm still trying to prove myself, but I know what I'm capable of, so I can't wait to get back on the ice so I can do that."
