What makes a good fourth line?  What is the fourth line’s job?  How do you measure its success?

At its most fundamental, a fourth line needs to play somewhere between about eight and a dozen minutes of hockey a night.  It doesn’t need to score, but it needs to dictate—to force play to the opponents end of the rink, to leverage its light ice time into energetic command of play, to through physicality and winning races and battles to leave an opponent in a worse state than it found them in.  A fourth line can also offer us a window into a team’s desired identity through short bursts of a game plan simplified and distilled for them to thrive.

With the bulk of the offseason’s reshuffling done, the Red Wings’ fourth line is taking on new character from the one it occupied a year ago.  Daniel Sprong and Robby Fabbri are out.  Joe Veleno and Christian Fischer are re-signed.  Tyler Motte has joined the effort.  And some combination of Nate Danielson, Jonatan Berggren, Carter Mazur, and Marco Kasper are lurking in the wings.

A year ago, Sprong and Fabbri spent a significant portion of the season as Detroit’s fourth line wingers, often with Veleno between them.  Neither player was a conventional fourth liner.  Both made their living on scoring.  They weren’t penalty killers by trade; they helped out on the power play.  At times, it served the Red Wings well.  At others, their willingness to trade offense for defense was exploited.

This year, with players like Fischer and Motte likely to wind up the two fourth line wingers (at least to open the year), Detroit will be adopting a more traditional approach to its last forward line, in keeping with an offseason’s objective of defensive tightening.

“We scored a ton more goals this year,” coach Derek Lalonde said at his end-of-season press conference. “We went from 26th to 13th in goals for. Those goals helped us, but we want to keep pushing, and you hope to get over that line. I still think it’s team defense and keeping it out of your net.”

Fischer, for his part, spoke about the painful way the end of the Red Wings’ ought to inspire change after re-signing: “I don’t think anybody was was too happy with how things shook out.  And obviously, that March really did us a disservice, but as athletes, as hockey players, I think every guy probably who was returning probably has a little bit more extra motivation this summer to do whatever, to take that next step in whatever it may be for your game, just to improve.”

Fischer suggested chipping in a bit more offense could be a way for him to provide that sort of improvement, but his primary impact lies in the work he does that doesn’t manifest in goals and assists.Motte, meanwhile, is one of the league’s best pure defensive forwards at five-on-five and short-handed.

So, for Lalonde, the fourth line should be able to provide something it couldn’t all too often a year ago: defensive stability.  That will likely be Detroit’s default option to close out its forward ranks, but even without Sprong or Fabbri, some of those youngsters should be able to add some offensive pop.

After the offseason departures of the likes of Sprong, Fabbri, Shayne Gostisbehere, and David Perron, the Red Wings will struggle to match last season’s raw goal total, but as Lalonde suggested, they should be able to improve their goals against.  That process can start with the fourth line.

Will it be enough to fight into the playoffs?  That won’t be determined in July.