BOSTON -

Montreal defenseman P.K. Subban felt almost an obligation to get the Canadiens a victory before the game went any longer.

Goaltender Carey Price's save count was pushing 50, and many of those shots could have easily given Boston a 1-0 lead in the second-round Eastern Conference playoff series. But Subban ended it with a goal 4:17 into the second overtime, giving the Canadiens a 4-3 win in the series opener on Thursday night.

"When a guy is standing on his head like that, you've got to find a way," Subban said. "It doesn't matter who it is. We had to find a way to win for him."

It was the second goal of the night for Subban, who blasted a slap shot from the blue line past Boston goaltender Tuukka Rask just seven seconds after defenseman Matt Bartkowski was called for holding Montreal center Brian Gionta. The Canadiens made quick work for their second power-play goal of the night and a 1-0 lead in the series, which continues Saturday afternoon in Boston.

Right winger Rene Bourque had a goal and an assist and Price finished with 48 saves, including 15 in overtime.

"We just gutted it out. It was a hard-fought game and could have been either way," Price said. "I don't want to sit here and point out things that I did well or individual efforts. I think tonight was a full team effort."

Rask finished with 28 saves for Boston, which rallied from deficits of 2-0 and 3-2 but never led. The score remained 3-3 after the first overtime. It was a fitting start to the 34th playoff series between the longtime rivals who went into OT for the 38th time in their 171 postseason matchups.

"I don't think we deserved to be down 2-0, but part of that was my fault," Rask said. "We battled back and it was great to see. It never should have been in overtime."

Boston defenseman Zdeno Chara had a great chance to end it about six minutes into the first overtime, poking a rebound behind Price, but the puck bounced across the crease without crossing the goal line.

Price got his right pad out in time to stop an open look from in front by left winger Brad Marchand with about 10 minutes left in the first overtime. Rask answered at the other end with a stop on a one-timer from the crease by center Lars Eller with about six minutes remaining.

Defenseman Johnny Boychuk scored with 1:58 left in the third period, tying it at 3-all and setting up overtime on Boston's third goal of the period. The Bruins rallied from a 2-0 deficit after two periods to tie it on goals by winger Reilly Smith and defenseman Torey Krug.

"We were pushed back on our heels a little bit in the third. They came with home-ice pressure," Price said. "They're a relentless team. They pushed back and worked their way back into the hockey game. At that point of the hockey game, we all realize that it's still up for grabs."

Montreal defenseman Francis Bouillon put the Canadiens back in front on a goal 7:51 left, but the Bruins continued getting pressure on Price and got one more past him on Boychuk's one-timer slap shot from the blue line off a pass from Marchand.

Marchand ended up with a penalty at the end of the third when he objected to Eller firing a shot at Rask after the horn and delivered a cross check to the Montreal center. Marchand was called for cross checking and Eller for unsportsmanlike conduct.

Bourque's fourth goal of the playoffs put Montreal up 2-0 early in the second period. Montreal pounced on a turnover in the neutral zone and started in on a 3-on-1 with Eller passing the puck back to Bourque for an unscreened wrist shot past Rask.

Subban beat Rask with a high wrist shot from the blue line to give the Canadiens a 1-0 lead with 8:37 left in the first period. Montreal was on a power play after Bartkowski was called for tripping 10:05 into the period. It was the first goal of the postseason for Subban, who had five assists in Montreal's first-round sweep of the Tampa Bay Lightning.

Rask said he should have stopped both shots by Subban.

"The first one and the last one," Rask said. "I saw enough of that last one to catch it. I don't know."

NOTES: The Canadiens and Bruins opened their 34th postseason meeting and first since Boston rallied to win in the opening round of the 2011 playoffs in seven games. ... The winner of the first game between Montreal and Boston has gone on to win 27 of the 33 series. ... Montreal RW Brian Gianta was playing in his 100th career playoff game. ... Montreal C Lars Eller got an assist in the second period and has at least one point in all five postseason games for the Canadiens.