By Matt Kalman, CBS Boston

BOSTON (CBS) — For all of their recent success in winning nine of their past 13 games (despite losing their past two), the Bruins still have a second-line crisis.

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Center David Krejci is finally healthy enough to be in the lineup every night and produce, but he just hasn’t had the same players on his wings consistently. And the players who have had a chance to play with one of the NHL’s premier playmakers have often played below the standard necessary for a second-line player in this league.

The most recent players coach Bruce Cassidy tasked with playing on Krejci’s wings — while Anders Bjork was scratched — were rookie Jake DeBrusk and natural center Ryan Spooner on Saturday in the 3-2 overtime loss to the New York Rangers. The trio actually combined on a goal, with Spooner and DeBrusk both driving to the net after Krejci gained the zone, and Spooner cashing in from the top of the crease after a pass from Torey Krug.

Unfortunately for the Bruins, they entered the zone offside and the goal was erased. To exacerbate the misfortune, DeBrusk and Spooner weren’t the same the rest of the night. DeBrusk wound up with his ice time cut down to 7:43 for the night, as Cassidy again lamented the left wing’s lack of strength of the puck and competitive edge in battles (a complaint that’s been leveled against DeBrusk before and was a major reason for Bjork’s exile to the press box Saturday). Spooner played 17:20 but just 9:21 of that time was at 5-on-5 and somehow he managed to play that much while failing to land a shot on net.

This season, six of Krejci’s 14 points have come on the power-play, meaning there’s a 5-on-5 production deficiency going on with his line.

If the first step toward solving this problem is admitting it exists, Cassidy is on his way to fixing it.

“It’s not ideal for David. We decided to leave [David Pastrnak] up [on a line with Patrice Bergeron and Brad Marchand] so he’s getting some kids, he’s getting Ryan Spooner, who’s a centerman but thinks the game a lot like David. So I think they could complement each other,” Cassidy said. “So yes, David’s been patient and we appreciate it, until he finds the right complement.”

The original sin of this situation was the drop-off of Matt Beleskey from high-priced free agent signee to American Hockey League mentor. Since returning from a knee injury last season, Beleskey was a shell of his former self and his deterioration culminated this week with his demotion to the Providence.

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The Bruins gave Beleskey as much of a chance as they could to get up to speed without putting standings points at risk or hindering the development of younger players (especially when half the lineup was out with injuries). Had he found his groove, maybe he wouldn’t have been an attractive to play on Krejci’s left side. But Beleskey would at least be able to play next to Riley Nash and David Backes (on one heck of a Crash Line) and allow Danton Heinen, the rookie forward with the most well-rounded game and the most experience, to try his hand on Krejci’s left or right. Now the Bruins’ depth has thinned out because of the inconsistency of the younger players who beat out Beleskey for regular playing time.

When it was suggested by this reporter that pairing Heinen with Krejci may be beneficial, Cassidy acknowledged he wasn’t against that idea and the Bruins have discussed it. But with the Heinen-Nash-Backes line playing well (even while miscast as a second line) and the Bruins trying to end the revolving door around Krejci, for now the Bruins are more likely to see if some combination of Bjork, DeBrusk and Spooner can provide Krejci with a legitimate match, which so far hasn’t happened.

One game in the press box may have been enough to teach Bjork his lesson. And considering DeBrusk’s down night against the Rangers, the Bruins could swap the rookies’ positions and see if Bjork can get back to basics and provide the net-front presence Cassidy wants from Krejci’s wings.

“Especially if I’m playing with a guy like Krejci, I think my focus will be trying to play simple,” Bjork said Sunday after an optional practice. “He  just he creates so much that you kind of just have to make the simple, right play all the time and the times I’ve played with him, when I’ve done that, we’ve been successful. So I think that’s something I’ve learned.”

At some point, Cassidy might have to move Heinen up the depth chart. DeBrusk or Bjork may benefit from playing a more straight-line game with Nash and Backes. The Bruins should get Peter Cehlarik back from injury soon, and he’s had chemistry with Krejci in the past. Jordan Szwarz showed a nose for the net in his brief Boston stint and if things get desperate the Bruins may have to put him, or maybe Austin Czarnik, on Krejci’s right and tell him to just crash the net.

There’s still time for the Bruins to solve their second-line problem internally. As we get toward the trade deadline, though, general manager Don Sweeney may have to consider another Drew Stafford-type rental just to put a veteran that could get the hot hand at the right time on Krejci’s side.

For sure the current situation isn’t fair to Krejci, who seems healthy and is still in his prime (albeit on the back end of that prime). And the situation is not fair to the Bruins, who have their sights set on a deeper run in this spring’s playoffs, if they don’t have a four-line attack to compete with the cream of the Eastern Conference.

The Bruins have gotten this far without a second line; imagine how dangerous they’ll be if they find the right complements for Krejci.

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Matt Kalman covers the Bruins for and also contributes to and several other media outlets. Follow him on Twitter @MattKalman.