Brad Marchand scored his league-leading 36th goal of the season and David Backes returned after getting hurt to score the game winner and the Boston Bruins defeated Calgary 5-2 on Wednesday night to end the Flames' 10-game winning streak.
Marchand is also tied with Chicago's Patrick Kane and Edmonton's Connor McDavid for the top spot in the NHL with 76 points.
Backes got tied up with Flames defenseman Mark Giordano and was taken into the corner boards 12 minutes into the game. He was favoring his leg as he was helped off the ice.
But he returned seven minutes into the second period and on his second shift back he broke a 2-2 tie. Backes took a pass from David Krejci on a 3-on-2 and from 30 feet whipped a wrist shot over the glove of Chad Johnson.
David Pastrnak scored twice, and Matt Beleskey also scored for Boston. The Bruins' fourth straight win moves them within three points of the second-place Ottawa Senators in the Atlantic Division.
Alex Chiasson and Dougie Hamilton scored for Calgary.