This season, they have been relying on showing up for just the final 20 far too much.
Granted, the Bruins have dominated that final frame. With another two-goal rally in the third period on Tuesday for a 4-3 win over Ottawa, the Bruins have now outscored opponents 71-33 in the third period this season. That plus-38 differential is better than the differential of every team in the league except Detroit for all three periods combined.
"We definitely know we can come back if we put our heads into it," Bruins defenseman Dennis Seidenberg said. "We do have the confidence, but you don't want to rely on that. You just want to play a 60-minute game, which we didn't do in a few games."
The Bruins certainly didn't do that on Tuesday. For the better part of two periods, they were dominated by the Senators. That was especially true in the middle frame, when Ottawa outshot the Bruins 13-5 and outhit them 15-7. Only a last-minute goal by Milan Lucic on one of the Bruins' few forays into the Ottawa zone kept Boston within striking distance heading into the third.
"[That was] huge," Seidenberg said of Lucic's goal. "We know we played a terrible second period, they scored on us a few times on breakdowns in the neutral zone and the defensive zone and for us to get momentum going into the third definitely helped us come back in this game.
"We were hesitant, we didn't play a clean game," Seidenberg added. "We kept turning pucks over, and that just played into their hands. The third period we decided to skate and decided to be the aggressors, and that ended up well for us. We scored a few goals and somehow we ended up winning."
The Bruins ended up winning because they finally started playing like the Bruins again.
"We started playing like ourselves in the third," Bruins forward Brad Marchand said. "We did a great job finding a way to win and at the end of the day that's what matters. We have to clean up different parts of our game and get back to where we were playing in the third but we just have to build on how we played on the third and hopefully continue that in the next game.
"I think we went back to the system," Marchand added. "Everyone started to buy in, we were playing our system, forechecking the way we can and guys were backing each other up and coming back hard and when we do that we're very tough to play against. It's what we have to learn how to do on a 60-minute basis."
The Bruins have proven repeatedly that they can be successful when they stick to that system. But despite the tangible proof of the results that kind of sustained effort produces, they continue to suffer lapses until their backs are against the wall in the final period.
"Well, it's the last try, the last hope if you don't play well," Seidenberg said of why the Bruins have performed so well in the third. "But you can't rely on coming out on top. You just have to be more focused and better in the first couple of periods and try to go into the third with a lead. We just have to be better like that."
Seidenberg's defensive partner Joe Corvo agrees, and hopes that the lesson is finally sinking in.
"For some reason we decided to go out in the third and we all played together," Corvo said. "That's the way when we play how we're supposed to play, we're on them forechecking and you're going to see pucks turned over and they're going to get it back to us at the point and we're going to get more chances to shoot.
"We need to maybe play three periods like that," Corvo added.
Corvo noted that after the struggles in the second period, the Bruins finally decided they couldn't allow their play to slip any longer.
"I think in the room, we just feel like enough is enough," Corvo said. "We're just tired of playing scattered hockey out there, nothing really structured. We just collectively decided to go out there and put our best foot forward. Usually it turns out well because the other team is just trying to hold on in the third anyway."
It may be the case that the Bruins have been able to catch some teams trying to sit on leads, but they can't rely on always being able to dig out of these late holes.
"It's like playing with fire," Corvo said. "I don't know how long we can get behind going into the third and expect to be coming back in these games. It almost feels like we're waiting for the third to come around, if we can just stay close and play our standard third period then we'll win the game. But like I said, that type of play doesn't last very long."
And teams that try to get away with showing up for just one period a night don't last very long when the stakes are raised come playoff time. The Bruins have 34 more games to work some more consistency into their efforts, and get their game back to where it needs to be if they want to enjoy a lot more third periods this spring.
"I think as a team we haven't been playing very well," Corvo said. "I think it's pretty obvious. We haven't been able to put together very many complete games, if any. It definitely doesn't feel like our game, like our brand of hockey. Hopefully it's just a lull. We'll get over it and be peaking at the right time going into the playoffs."
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