BOSTON -- David Backes couldn't help but smile after scoring his first goal of the season in his first game in nearly a month.

The Bruins right wing picked a big moment against a big-time rival to accomplish the feat.

Backes scored the deciding goal with 9 minutes, 31 seconds left in the third period, David Pastrnak added his league-leading 25th goal, and Boston won its seventh consecutive game, beating the Montreal Canadiens 3-1 on Sunday night.

"You could see [the emotion] on my face. That was elation,'' Backes said. "I've been watching this team do this for a month, and now it's great to be part of it.''

Backes' goal came off a feed from David Krejci through the right circle. Jake DeBrusk added his sixth goal of the season on a give-and-go with Charlie Coyle a couple minutes later and the Canadiens' season-high losing streak reached eight (0-5-3).

Backes was in the lineup for the first time since being injured during a scary collision with Ottawa's Scott Sabourin on Nov. 2.

"We didn't know what he'd have, to be honest with you,'' Bruins coach Bruce Cassidy said. "He hadn't played in a while. I thought he gave us some good energy, had a couple looks, was banging bodies.''

Tuukka Rask made 28 saves for the Bruins.

Boston extended its points streak to 11 games (8-0-3) and entered the third month of the season as the only team without a home regulation loss (11-0-4).

Joel Armia scored and Carey Price had 31 saves for Montreal.

"For 45, 46, 47 minutes, we were playing solid hockey,'' Montreal and former Bruins coach Claude Julien said. "We needed that win desperately, and now we've got to go back home and find a way to win the next one.''

Montreal had allowed 24 goals in four prior games, including a season-worst 8-1 loss to Boston at home Tuesday that featured a hat trick by Pastrnak.

Price gave up five goals on 11 shots in Tuesday's loss to the Bruins and has surrendered 19 total over his past four games.

But the Canadiens star saw improvement in his team's effort.

"If we definitely play like [we did today], the majority of our games are going to be a better result,'' Price said.

The Canadiens got off to a fast start this time after giving up three first-period goals in Tuesday's matchup.

Armia's backhand shot from the right circle deflected off Charlie McAvoy's skate and into the net for his 10th goal of the season 1:58 into the game.

Play was stopped with 2:47 left in the second as a scuffle broke out involving all 10 position players on the ice after Shea Weber interfered with Pastrnak.

Pastrnak evened the score at 6:16 of the third after skating into the right circle and firing a one-time shot past Price high to the stick side.

"Twenty-five [goals] by December 1st, I wouldn't have predicted that,'' Cassidy said. "I know he's certainly, maybe could have had 30. I don't think he's had a lot of freebies, let's put it that way.''

Backes' goal came with 9 seconds left on a Bruins' power play after Montreal's Nick Cousins was whistled for holding Boston's Torey Krug.

"It's unfortunate. It was a bad call,'' Julien said. "Krug's stick was stuck under his own player. As a referee in a 1-1 hockey game, you've got to make sure when you make those calls. I was pissed off at the way that was handled.''

The Canadiens beat the Bruins 5-4 in their first meeting on Nov. 5 in Montreal.

NOTES: Bruins LW Brad Marchand played despite being a game-time decision after playing through flu-like symptoms on Friday. ... Boston C Patrice Bergeron (lower body) was out for the sixth time in eight games. Bergeron skated before Sunday's practice and is still day-to-day. ... Canadiens D Victor Mete did not travel and was to be reevaluated Sunday after suffering a lower-body injury Saturday against Philadelphia. ... Montreal LW Jonathan Drouin (torn tendon in left wrist) has missed eight games following his surgery but has been medically cleared to ride a stationary bike. His return date, originally thought to be eight weeks, is still uncertain. RW Paul Byron (knee) also missed his eighth straight. ... Canadiens legend Guy Lafleur underwent surgery Thursday in Montreal to remove ganglions and a lobe on his lung, the team announced Sunday. LaFleur is expected to return home soon to continue his recovery.

UP NEXT

Canadiens: Host New York Islanders on Tuesday night.

Bruins: Host Carolina on Tuesday night.