Montreal's Ben Chiarot scored the tiebreaking goal in the third period as the host Canadiens snapped red-hot Boston's six-game winning streak, beating the Bruins 5-4 on Tuesday.
Chiarot zipped a shot that goalie Tuukka Rask stopped briefly, but the puck rolled in for the defenseman's second goal at 9:06.
Victor Mete scored twice, Tomas Tatar posted a goal and an assist, and Paul Byron also tallied for the Canadiens, who won for the fourth time in five games.
Jeff Petry recorded two assists, Chiarot added an assist for a two-point night, and goalie Carey Price made 21 saves.
Montreal's Claude Julien coached his 1,200th career NHL game.
Boston's David Pastrnak extended his career-best point streak to 13 games with his NHL-leading 15th goal. Torey Krug notched an assist on the goal for his 300th career point.
Connor Clifton, Anders Bjork and Sean Kuraly scored, and Rask (26 saves) fell to 7-1-1.
Zdeno Chara played in his 1,500th NHL game -- the sixth-most by an NHL defenseman. He became the third active player to reach the milestone, joining Joe Thornton and Patrick Marleau.
Montreal started out hot right away by scoring 73 seconds after the puck dropped on the 923rd meeting, including playoff games, between the Original Six clubs.
Mete fired in the first marker after Petry's centering pass caromed back into the slot, but Mete committed a hooking penalty at 14:49, putting Boston's power-play unit -- the top one in the NHL -- onto the ice.
On Boston's faceoff win, Krug slipped the puck to Pastrnak at the left circle, where the right wing buried a one-timer six seconds into the man advantage.
However, Tatar completed a two-on-one with a wrister that clipped Rask's glove and went in for his fifth goal at 16:45.
Byron made it 3-1 just 31 seconds later when he moved in on Rask and zipped a shot between the Finnish backstop's pads for an unassisted marker.
Clifton zoomed through the slot, dipped into the right circle and ripped his first regular-season NHL goal in his 32nd game at 7:17 to trim Montreal's lead to 3-2.
The Bruins evened it when Bjork found a rebound and scored his second at 18:13, but Mete scored 42 seconds later for a 4-3 lead.
Kuraly tied it 3:03 in the third after a strong shift following a Bruins power play.
Boston's Charlie Coyle appeared to net the go-ahead goal at 5:16, but Montreal challenged for offside, and the call was reversed.