The Bruins got their power play going and got under the Canadiens' skin as they won 4-2 to push Montreal to the edge of a playoff precipice.
Boston was crisp from the get-go and scored power-play goals 32 seconds apart early in the second period to build an insurmountable 3-0 lead.
"I don't think you can look at tonight and say all of a sudden we found our game." said Julien. "I think we were better tonight but there's another game to win and, I'm being honest here, it's not going to be easy."
Game 6 of the second-round playoff series is Monday in Montreal with the Canadiens needing a win to remain alive — undoubtedly regretting the Game 4 overtime loss at the Bell Centre that rejuvenated the Bruins.
Montreal, which outshot Boston 31-30, has trailed Boston three games to two five times before and come back to win three of those series.
After a five-year post-season drought with the man advantage against the Habs, Boston broke the power-play hoodoo through back-to-back strikes by Reilly Smith and Jarome Iginla. Tomas Plekanec was in the penalty box for both goals.
"I thought we were intent when we started the game but their power play gave them a lot of momentum and confidence," said Montreal coach Michel Therrien.
Boston was 0-for-10 in the series on the power play and amazingly had not scored in 39 tries with the man advantage against Montreal in the post-season since Game 2 of their 2009 Conference quarter-final.
"Our power play was due," Julien said by way of understatement.
After the first period, the talk was of the need for more intensity, winning more battles and making stronger plays on the power play.
It worked and Boston had the rare luxury of playing with a lead. The Bruins led for 46 minutes 40 seconds Saturday, some four times the 11:39 they were ahead during the first four games of the series. The Canadiens have held the lead for 106:11 of the series.
Carl Soderberg and Loui Eriksson also scored for the Bruins, who got a strong physical game from Milan Lucic. The hulking winger cruised the ice like a shark, looking for someone to take a piece out of.
A late P.K. Subban goal made the score closer than the game actually was. Brendan Gallagher also scored for Montreal.
Goalie Carey Price said the Habs are up for the elimination challenge.
"You back any animal into a corner, it's going to be desperate," he said calmly. "I think we're going to be a desperate hockey club coming into next game and I think we're excited for the challenge."
Game 7, if needed, would be next Wednesday in Boston.
The Canadiens will need to take a deep breath before the puck drops at the Bell Centre with their season on the line.
"Frustration or not, we've got to make sure we play with some more composure," said a tight-lipped Therrien.
Subban complained after the game of being sprayed with water twice from the Boston bench late in the game. After raising the issue in his post-game scrum, he tried to downplayed the antics but it clearly bothered him.
"It hit me in the visor. I couldn't even see the last minute and a half out there," he said. "So I was pretty upset about that ... I'm sure if that was me that did it, it would be a different story. I'd probably be on the news for the next three days."
Therrien, who looked like he had sucked a lemon prior to taking the podium, had little to say about hockey's version of Watergate.
"Yeah, we saw that," he said when asked about the water spraying.
"I don't want to comment on that," he added when pressed on the matter.
Julien said he didn't see it and wouldn't condone it.
After two games that features a total of five penalties, the referees remembered to bring their whistles with them Saturday and called 11 penalties.
Montreal was 2-for-5 on the night with the man-advantage but was 0-for-3 in the first period.
"I strongly believe that if we would have gotten a goal on one of those first power plays, it could have been the difference in the game," said Subban.
Therrien, meanwhile, said his team had to be better five-on-five.
The line of Soderberg, Eriksson and Matt Fraser finished with two goals and three assist and was plus-six. The Bruins third line has now scored three of Boston's last five goals with Fraser accounting for the overtime winner last Thursday in Montreal.
Soderberg was awarded the Bruins jacket, a hand-me-down from Boston legend Johnny Bucyk, as the team's player of the game.
The capacity crowd of 17,565 at TD Garden had plenty to cheer about.
Boston looked focused and physical, outhitting Montreal 39-29. Plus the Bruins managed to plug up Montreal's shooting lanes.
"It was one of those games where were just on the wrong side of the puck all night," said Canadiens captain Brian Gionta.
Smith hit the post before either team registered a shot.
The Bruins went ahead at 13:20 of the first period after Eriksson beat the lumbering Douglas Murray to the puck behind the net and sent it straight back to Soderberg, who banged the puck in off Price's pad for his first career playoff goal. It came on Boston's sixth shot of the night.
It was a good omen for the Bruins, given the team scoring first won the first four games of the series and the Bruins were 5-0 in the playoffs — and 41-6-2 during the regular season — with the first goal.
Then came the power play breakthrough as the Bruins dominated the second period.
After some good puck movement had the Canadiens running around, a Dougie Hamilton shot from the point deflected in off Smith's foot. Then, after a Bruins faceoff win, a nifty Torey Krug pass from the wall found Iginla all alone and he snapped a shot past Price.
Boston was bossing the game and the Habs began to lose some of their composure.
But Plekanec made up for some of that time in the penalty box when he snapped a shot from the faceoff dot that went through a Boston defenceman's legs before rattling in off Gallagher at 14:39 on the power play to cut the lead to 3-1.
The five-foot-nine Gallagher got thumped in the corner seconds before on the play, but picked himself up and got in front of the goal to be in position to tip the puck in.
The goal ended Tuukka Rask's shutout streak of 122 minutes six seconds.
The Bruins kept up the pressure in the third, coming at the Canadiens. Boston calmly blunted Montreal attacks and then moved the puck up ice with speed and purpose.
Eriksson's goal, with 5:48 remaining, came on a three-on-two complete with some slick passing. Price denied Fraser but was powerless to stop Eriksson, who skated around him until he had a clear shot at an empty net.
With Matt Bartkowski off for holding and Price on the bench, Subban scored from the point to make it 4-2 with 2:29 remaining.
Therrien brought back Brandon Prust, who had sat out the last two games. Making way was veteran Daniel Briere who had played under 10 minutes each of the last three contests.
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