MONTREAL - The Montreal Canadiens have little time to savor their latest successful effort at staving off playoff elimination.

They've got another do-or-die game coming right up. And now, so do the Boston Bruins.

Michael Cammalleri and Brian Gionta each scored 5-on-3 goals and Montreal beat the Bruins 2-1 on Tuesday night, forcing a seventh game to decide their first-round series.

"In less than 24 hours we've got to do it all over again and tonight gets forgotten really quickly depending on the result (Wednesday) night," said Cammalleri, who scored in the first and assisted on Gionta's goal in the second.

Game 7 is Wednesday night in Boston, which is bidding to win for just the ninth time in 33 playoff meetings between the longtime rivals.

"It's win or you're done," said Bruins goalie Tim Thomas, who stopped 25 shots. "If we play the same way we did to win the three, we'll win the fourth."

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The Canadiens improved to 6-1 in playoff games where they have faced elimination dating to last year's run to the Eastern Conference final.

"It's a lot better coming in here knowing we're going to Boston than coming in here knowing that we're going home," said Montreal's Carey Price, who stopped Rich Peverley's short-handed chance with just over 2 minutes remaining and made 31 saves. "We can't dwell on it, though. We've got to saddle up and do it again (Wednesday)."

The Canadiens had lost three in a row, including the previous two in overtime, after winning the first two games on the road.

Dennis Seidenberg scored for Boston, which played more than half the game without ejected winger Milan Lucic but still outshot Montreal 32-27.

"Obviously when it's 5-on-3 it's harder to keep the puck out of the net," Thomas said.

The Bruins went 0 for 3 on the power play and have yet to convert a chance in 18 opportunities through the first six games.

"The power play's been struggling and they won the game because of that tonight, because of their power play," center Patrice Bergeron said. "We've got to find a way and bear down."

Lucic was given a boarding major and a game misconduct 4:37 into the second for his hit on Jaroslav Spacek. The Bruins' 30-goal scorer drove the Montreal defenseman's head into the glass on a check from behind directly in front of the off-ice officials.

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"I haven't had a chance to really look at it closely; you see quick replays here and there, but it's something I need to see before I'm able to comment on that," Bruins coach Claude Julien said.

The Canadiens got their second lengthy two-man advantage of the game 16 seconds later when Bergeron was penalized after his clearing attempt sailed over the glass.

Gionta, who had a goal disallowed in the first, got his third of the series at 5:48 on the ensuing two-man advantage to restore Montreal's one-goal lead at 2-1.

Spacek, who was bleeding and laid on the ice in obvious pain before he was attended to by a trainer and helped off, later returned to the Canadiens' bench.

The crowd of 21,273 booed as a Montreal goal 3:27 in was disallowed due to a quick whistle. Scott Gomez's dump-in was misplayed by Thomas and lay clearly open beside him as Gionta slipped it in the net.

Cammalleri was the catalyst for the opening goal as he threw the puck toward the Boston bench and caught the Bruins with too many men on the ice, then had his stick slashed in two by Seidenberg for a two-man advantage. Cammalleri one-timed a pass from P.K. Subban inside the near post from the right circle at 10:07.

The Bruins struck back with the teams each down one man only 48 seconds into the middle period as Seidenberg came out from behind the net and lifted it inside the post.

Brad Marchand had a chance to draw Boston even for a second time late in the second but he misfired on a chance at a wide open side during frenzied play while both teams were a man short.

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NOTES: The ice was littered with promotional towels after the disallowed goal, prompting a warning that the Canadiens would be subject to a minor penalty if the crowd caused any further delays by throwing objects on the rink. ... Yvan Cournoyer brought out the Canadiens' torch to begin the pregame presentation. ... No team has won a playoff series without scoring a power-play goal since Anaheim swept Detroit in the first round in 2003. ... Price had lost each of his previous seven playoff starts at the Bell Centre dating to 2008. ... D James Wisniewski and C David Desharnais did not play for Montreal and were replaced by Yannick Weber and Paul Mara. Both suffered undisclosed injuries during Game 5. ... Canadiens C Lars Eller left early in the first after suffering an apparent right shoulder injury but returned late in the period.