The Bruins’ 19 goals so far this season rank 18th in the NHL, and the thought of where Boston would sit if not for the top line’s production must frighten head coach Bruce Cassidy.

Of those 19 goals, 14 have come from either David Pastrnak (eight), Brad Marchand (four) or Patrice Bergeron (two). Torey Krug, Zdeno Chara, Joakim Nordstrom, Danton Heinen and Brett Ritchie have the other tallies. Despite the scoring disparity, Boston’s 11 points in the standings are good for fifth in the NHL.

While the Bruins’ success despite an utter lack of secondary scoring is impressive, it sure isn’t sustainable, and that’s not lost on Boston’s head coach.

“Well, we win the game, right, tonight, if we get secondary scoring from anybody,” Cassidy said after Boston’s 4-3 shootout loss to the Tampa Bay Lightning on Thursday. “I think we’re stating the obvious saying that. Having said that, our record is pretty good without it, but I don’t think it’s sustainable.”

Any number of factors can be attributed to the way things have begun for Boston’s offense. Jake DeBrusk is on a rough — albeit unlucky in some respects — goalless drought to kick off the campaign, and injuries to David Krejci have forced players into atypical roles on two occasions. Karson Kuhlman by no means has been bad on the second line, but he hasn’t helped generate much in the way of great chances — the DeBrusk-Krejci-Kuhlman trio in 39:03 ice time this season has just six high-danger scoring chances and haven’t cashed in on any of them, per Natural Stat Trick.

The common denominator in much of this seems to be the second line figuring it out.

So how does that get fixed?

Of course, it begins with getting Krejci healthy, as his upper-body injury kept him out of Thursday’s game. But in addition, many point to Anders Bjork. The winger is slashing 3-3-6 in five AHL games this season and in years past has shown good stretches at the NHL level when healthy. Arguably the only reason he’s not on the roster right now is because he’ll get more ice time in Providence than he would in Boston. Calling him up would be a move that reeks of panic this early in the season, and throwing him into a second- or third-line role right away might not magically fix all of the Bruins’ problems.

Here’s one potential issue: As Mark Divver, a freelance journalist who covers the Providence Bruins closer than anyone, points out, Bjork (a left shot) is playing on the left side in the AHL right now. He’s played mostly on the right in the NHL, so actually allowing him to play on his strong side might help him out on his next call-up. But in doing so, it likely would require moving an already struggling DeBrusk or Heinen, who goes through lengthy scoring droughts, to their off side. They both can do it, but at what point would Cassidy be messing with too much in hopes of making something that’s no sure thing work?

This issue hardly is a new one, either. It’s this very problem that prompted Don Sweeney to go out and get Marcus Johansson, a true middle-six winger, at the trade deadline last February. It was a great move, but Johansson is in Buffalo now and the Bruins are back to square one. Obviously, it’s way too early to make a remotely dramatic move, but the Bruins can’t go on like this forever. Eventually, the top line will slow down, and the last time that happened the Bruins lost in the Stanley Cup Final to the St. Louis Blues.

Who knows, maybe Bjork is the answer. Or maybe the fix is outside the organization. But in the interim, the Bruins will just have to grind things out with a revolving door of players on the right wing. One potential target that was discussed as a good fit on the latest NESN Bruins Podcast was Devils winger Blake Coleman, who might be attainable if New Jersey struggles to get on track.

Thursday’s loss, as Cassidy noted, shows the perils of secondary scoring struggles. That hasn’t hurt Boston in the standings so far, but it seems clear to all that the Bruins won’t be able to continue on this track for months.

Thumbnail photo via Bob DeChiara/USA TODAY Sports Images