Few Maple Leafs have been as important to success as David Kampf

Who?

That was the reaction from hardcore Toronto Maple Leafs fans and generalists alike when David Kampf signed a multi-season free-agent contract with the club mere hours after the window opened last summer.

He was a relative unknown in most hockey circles after he notched one goal in an uneventful and otherwise inconsequential season for the barren Chicago Blackhawks. Impossibly, it seemed, it was his fourth full season in the NHL. He had yet to make a mark.

Assuming there is one, credit to the Chicago-area scout who sat through countless hours of Blackhawks hockey and presented their case on Kampf to Kyle Dubas and the Maple Leafs braintrust. Because advocating for and ultimately unearthing this unknown commodity has been as important as any move the Leafs made in their wildly successful offseason remodelling.

Kampf has been as important as almost any other player in the process of building a 2-1 series lead over the Tampa Bay Lightning in their first-round matchup.

However it went down, it does say something about the Leafs' process that Kampf was prioritized at the outset of free agency. This wasn't a player found on big boards or spoken about on radio or television. There was no proven postseason track record, or a reason to believe in any offensive upside. Even the defensive metrics were, at surface level, nothing to really be too excited about.

But there was enough information, for the few looking hard enough, to believe in his ability to serve as a defensive ace on a shutdown third line.

This was a dynamic Sheldon Keefe had long believed was the missing piece in Toronto. The Maple Leafs head coach indicated very early in his tenure that a defensive element in his forward scheme was essential, and that players like Kasperi Kapanen and Andreas Johnsson didn't do the sort of things he coveted in a third-line role.

For all the talk of innovation and progressiveness coming out of the Mike Babcock era, Keefe held old-school ideas for his third line. He wanted to support his ultra-talented top units with a checking trio which could routinely take the puck from the defensive zone to the offensive zone in matchups versus top competition.

Kampf isn't the only player who fills this ideal, but he does it best.

In a sea of constant change and lineup manipulation, Kampf has been the undying fulcrum for the checking unit.

And aside from Auston Matthews and Mitch Marner, not a single player has carried out their role for Toronto more effectively than Kampf.

Kampf was one of three players on the ice for more than 700 defensive-zone faceoffs in the regular season. In the five-on-five condition, Kampf and Edmonton Oilers star Leon Draisaitl were the only players in the top 10 of total defensive-zone faceoffs to turn in a positive expected goals percentage. Kampf leads that same select group in shot and shot-attempt share, and managed a positive goal differential despite such a heavy defensive load. With the defensive metrics he was without in Chicago now with the Maple Leafs, the data behind Kampf's performance could be extrapolated to suggest that he's the single-most reliable forward in spoiling the offensive-zone opportunities of top competition.

Kampf was also just one of four forwards to log over 200 minutes on the penalty kill during the regular season. Like his work at even strength, his defensive metrics compare to just about any other regular killing penalties league-wide.

"He's a lot of fun to be out there with on the penalty kill," Marner said of Kampf after Game 1. "He's so smart with his stick position, obviously on faceoffs he's a bull — he can win a lot. The communication with him is high. He's not afraid to get in lanes, break up passes, step up in the neutral zone.

"He's done a great job for us all year long."

Suffice to say, Kampf's areas of expertise are extremely handy in the situation the Leafs find themselves in now. Tampa Bay has a collection of some of the most talented forwards in the game which, in turn, come together to produce a lethal power play and one that's in some ways set the standard across the entire NHL.

The work of Kampf and the other killers was, in large part, the story of Toronto's Game 1 win last Monday.

Kampf led all Leafs skaters with seven minutes and 22 seconds of shorthanded ice.

He had the only goal inside those critical minutes.

All told, in a series in some ways defined so far by special teams, Kampf has logged a series-high 15 minutes down a man. Where it hasn't necessarily gone fully to script for Kampf has been at even strength.

More often than not, both coaches have endeavoured to match their top two scoring units against each other, leaving Toronto's defensive ace to work elsewhere. Priorities have seen Kampf take on a wider array of matchups, with Tampa's third line of Ross Colton, Nick Paul and Brandon Hagel being the most common overlapped opponent.

Freed from taxing defensive minutes at times, and in late-game scenarios saddled with them like he was in Game 3, his full game has been on display.

The sum of that is responsibility for both building and protecting the leads Toronto has had in the series.

His second goal in three games Friday night in Tampa, which was once again a total individual effort, was not only the difference in the game, but one of the few times a Leaf has beaten Andrei Vasilevskiy cleanly.

With as many goals as Matthews, more high-leverage defensive minutes than most defencemen, the steadiness of production no matter his opponent or linemates, Kampf has been just as important as any Leafs skater in the process of building a 2-1 series lead over the two-time defending champions.

Not bad for a player who had no fans and a lack of support in the raw moments when he was first brought aboard.

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