Bruins defenseman Johnny Boychuk levels Rangers forward Derek Dorsett during Thursday night's Game 4. (AP)

NESN Bruins analyst Barry Pederson joined Dennis & Callahan on Friday to examine the B’s mistake-prone effort that cost them Game 4 vs. the Rangers.

Tuukka Rask had the most glaring error when he fell and let the Rangers break through with a cheap goal that cut the B’s lead to 2-1 in the second period.

“It’s one thing to give up a goal and kind of keep momentum. But the way that goal went in, with Tuukka falling flat on his butt and the puck going in, in one of the softer goals we’ve seen, that kind of started to change momentum,” Pederson said. “And then once [Zdeno] Chara gave up the other one it was as if kind of the floodgates opened up a little bit.

“But the Rangers still didn’t show me a lot last night. … It’s up to the Bruins. The Bruins are going to need a lot more intensity from their leaders. It wasn’t only Tuukka that I thought lost his concentration — because of probably lack of action — but also I didn’t think Chara, [Milan] Lucic and [David] Krejci, the three leaders that they’ve had so far this playoffs, I didn’t think they were nearly as intense as they had been. And that’s what makes it hard to win four games in a row. It’s not only the team that you’re playing is usually a little bit more desperate and playing with pride. It’s also the fact that you kind of let up a little bit.”

Added Pederson: “The Bruins just weren’t as intense and as focused as they need to be as a team. … You had the opportunity, you just let it slip through your fingers.”

Pederson said he was surprised at the effort — or lack thereof — from the Rangers.

“I didn’t see much at all from the Rangers last night that tells me, Oh, boy, this offensive juggernaut now all of a sudden is going to click; here they go. I thought it was a situation where the Bruins totally dominated the first part of that hockey game. I was shocked again at the end of the first period at how bad the New York Rangers looked. And then once the Bruins took that 2-0 lead I kind of felt like it was over and that the Bruins had complete control of this because the Rangers hadn’t showed us anything up to that point.

“So, the Bruins have to come home and be ready Saturday night right from the open, give the Rangers a reason to not show up. They have to bring that intensity level that they showed earlier on. I’m kind of counting on that, I think.”

On the Rangers’ winning goal in overtime, Chris Kreider shook off Dougie Hamilton‘s defense and redirected a Rick Nash pass past Rask. Pederson said Hamilton shouldn’t shoulder the entirety of the blame.

“He made a mistake, but I also thought that Chara backed in way too much,” Pederson said. “That was a two-on-three. Normally in those situations Z does not back in. When he has an outnumbered or even opportunity he goes right at the guy. I thought he backed in a little too much, gave Nash too much speed, and then of course Kreider was able to win the one-on-one battle with Dougie.”

That said, Pederson stuck with his earlier statements that Hamilton should be the first of the young defensemen to sit when one of the injured veterans is ready to return.

“When and if [Dennis] Seidenberg is healthy, he has got to play, he’s that good a player. He’s a bull out there, he takes ice time, big minutes, a physical presence. They need him,” Pederson said. “And I still stand that I thought that if they were going to make the move, Dougie Hamilton would be the first to be pulled, and then probably [Torey] Krug and then [Matt] Bartkowski. But I was very impressed with both Krug and Bartkowski again last night.”

To hear the interview, go to the Dennis & Callahan audio on demand page. For more Bruins news, visit the team page at weei.com/bruins.