The Canadiens were playing the second half of a back-to-back and were without Max Pacioretty (lower body) and defenseman Victor Mete (hand).
"I'm not going to complain about our guys' effort," Montreal coach Claude Julien said. "You know, it's our fourth game in six nights and we've been traveling, and we know the circumstances from [Friday] as well. We tried to hang in there and we played a really good hockey club first and foremost.
"At the same time, our goaltender, who was fresh from not playing last night, was giving us that opportunity. When you take six penalties, whether they're deserved or whatever the case may be, it eventually catches up to you and we did our best and eventually the fresher team and the better team won."
Gallagher scored at 9:16 of the first period to give the Canadiens a 1-0 lead. After he stole Kevan Miller's pass in the neutral zone, Gallagher skated in and beat Khudobin blocker side with a wrist shot from the high slot.
DeBrusk tied it with a power-play goal at 17:15 of the third period after he redirected Nick Holden's slap pass past Niemi.
"A guy [Montreal's Nicolas Deslauriers] lost his stick. I think that's a key part of it," Krug said. "No, I mean, it can be frustrating, you have so much time on the power play, you're not getting the goals. We had a lot of good looks. Ultimately it was just getting a shot into the slot and those guys do the work. Great job by those guys to stick with it."
