BOSTON – Irving Berlin wrote "How Deep is the Ocean?"

By the end of the Boston Bruins' five-game victory against the New York Rangers in the Eastern Conference Semifinals, Rangers coach John Tortorella had to be asking "How Deep Is Your Organization?"

The Bruins won Game 5 Saturday at TD Garden 3-1 on the strength of two goals by their fourth-line center, Gregory Campbell, and one score from a rookie defenseman, Torey Krug, who wasn't even on the team 10 days ago.

"I think they're a deeper team than we are, so we needed to play at a different level," Tortorella conceded after the defeat.

To call Campbell a fourth-line center is really only a way of describing the Bruins' depth chart. Nothing about the way Campbell and his linemates Daniel Paille and Shawn Thornton resembled a traditional fourth line in this series, other than their ruggedness and the two fighting majors they accumulated. For the series, they combined for four goals (three by Campbell) and 10 points. They were on the ice for both goals scored in Boston's Game 3 win in New York and Campbell's goal in Game 5 stood up as the game-winner.

When you consider that the Bruins got five goals from their other nine forwards, having an energy threesome like Campbell's trio comes in handy.

"I think what that does and you saw that [Saturday night], they are down by a goal, they have to cut down to three lines, which is the right thing to do obviously," Bruins coach Claude Julien said. "But with us having four lines, it's important. As long as you have the trust and you know those lines can do the job. It's about being a little bit more fresh and you hope that you win the race as you win the battle because you are a little bit more fresh. So, when we can do that, that's great. I think it played a big role in this series."

The Bruins' display of depth didn't stop up front against the Rangers. With veterans Dennis Seidenberg, Andrew Ference and Wade Redden forced out of the lineup by injuries, the Bruins had to turn to rookie Torey Krug, Matt Bartkowski and Dougie Hamilton to fill the void. Krug finished the series with 4-1-5 totals, while Bartkowski recorded an assist and formed a solid second defense pair with veteran Johnny Boychuk.

It's a credit to Boston's depth that with Seidenberg's return to action for Game 5, the Bruins sat out Hamilton, who'd recorded three assists and a plus-2 rating in the first four games. Meanwhile, the Rangers lost defenseman Anton Stralman to an injury and had to fill in with 39-year-old Roman Hamrlik, whose two giveaways helped lead to Campbell's game-winner.

"Yeah, I think that's probably the biggest storyline of the series is how they were able to step up and you see [Krug] stepping up with four goals in a series," Bruins forward Milan Lucic said. "That's huge and having to play against two huge guys like [Brian] Boyle and [Taylor] Pyatt and being able to shut them down and also Bartkowski stepping up with Johnny playing against that [Ryan] Callahan line, that's been successful all year. It's great to see so, it's great to see them playing with a lot of confidence and they're going to need to keep bringing it in order for us to be successful."

Now the next test for the Bruins will be the Eastern Conference Finals and a Pittsburgh Penguins team that Lucic compared to the Miami Heat in terms of depth and star power. The Penguins also have four lines that can thrive at both ends of the rink and a defense corps that can pop in a goal as often as it prevents one.

It's no secret that the Bruins' depth is going to be severely tested against the East's top seed.

"Of course. We've all watched Pittsburgh play," Campbell said. "We've played against them enough and we have a lot of respect for that team, the way they're coached, and they have four really good lines and guys that contribute and they got scoring from every line and they're not too far removed from winning the Stanley Cup. And they know how to win, so I think it will be a great matchup. We're excited about it, and we're going to have to be good."