Charles Hudon broke up Hutton’s shutout bid with a 6-on-4 goal with 1:07 remaining.
Barbashev snapped a scoreless tie with his second goal of the season early in the second period. He whipped a wrist shot from the top of the faceoff circle past goalie Carey Price, who fell to 14-18-4. Barbashev spent 21 games in the minors earlier this season.
“I’ve got a better pace since the start of the season,” Barbashev said. “It makes me feel more comfortable out there.”
Berglund pushed the lead to 2-0 with a power-play goal early in the third. He jumped on the rebound of a shot by Tage Thompson.
Steen added an empty-netter with 2:17 left.
Montreal is 2-4-2 in its last eight games and remains 10 points out of a playoff spot in the Eastern Conference.
“We’re not looking for moral victories, we’re looking for points,” Pacioretty said. “Really what we need are answers among ourselves about how to win hockey games.”
Montreal winger Paul Byron left the ice after being shoved into the boards late in the third period. Coach Claude Julien said the injury does not appear to be “overly alarming.”
NOTES: Montreal C Phillip Danault missed his seventh consecutive game with a concussion. … The Blues have earned at least one point in eight of their last 10 games against Montreal. … Canadiens D Joe Morrow returned to the lineup in place of Jordie Benn. Morrow had been a healthy scratch in the previous seven games. … The Canadiens recorded the first 11 shots of the game.