The fact that a Pittsburgh Penguins team built around Sidney Crosby and Evgeni Malkin is appearing in its first Stanley Cup Final in seven years speaks to the level of depth and amount of good fortune needed to succeed in today's NHL.

Thanks to some impressive on-the-fly retooling by second-year general manager Jim Rutherford, the Penguins have been able to roll out four effective forward lines through the playoffs. And while the defense has seen its share of issues, it's a new-look bottom pair that might prove to be the difference in a series against the San Jose Sharks.

Here's a look at three line combinations that will decide the Penguins' fate in the Stanley Cup Final.

'HBK'

One of the big stories of the playoffs so far has been Pittsburgh's 'HBK' line, and not simply because of the tie-in with former WWE superstar Shawn Michaels.

The trio of Carl Hagelin, Nick Bonino, and Phil Kessel is technically listed as the Penguins' third line, but they've played like a top unit for weeks now, outscoring all teammates not named Crosby or Malkin.

The line was created in light of an injury suffered by Malkin late in the regular season, and the chemistry developed coupled with the Russian center's return has given head coach Mike Sullivan the ability to deploy three legitimate scoring lines.

The opposition can only keep so many weapons from firing, and with attention duly paid to Pittsburgh's two elite centers, the HBK line will need to keep dropping sweet chin music in order for the Penguins to achieve their ultimate goal.

Kunitz - Malkin - Rust

In Game 7 against the Tampa Bay Lightning, Bryan Rust drove to the net like a car fresh off the lot, scoring both of his team's goals - with several other golden opportunities along the way - in the series-clinching victory.

The young right winger has found himself on a line with Malkin and Chris Kunitz, a makeshift second line created upon the center's return from injury, and a combination that Sullivan did well to stick with despite some ineffective play early in its tenure.

As the following chart displays, Kunitz led all players in terms of possession over the course of the Eastern Conference Final, with Rust and Malkin not far behind.

The success of this line late in the series against Tampa Bay, and particularly in Game 7, will make the Sharks question their defensive deployment, because, as has already been stated, there's only so much coverage to go around.

Cole - Schultz

A season-ending injury suffered by Trevor Daley in Game 4 of the Eastern Conference Final has brought Justin Schultz from the NHL's basement all the way up to hockey's biggest stage.

The former Edmonton Oiler, who was added prior to the trade deadline, had not seen NHL playoff action prior to this season, and is averaging only 13 minutes of ice time through nine postseason games.

Schultz did, however, record a pair of assists against the Lightning, and has been a positive possession player with a Corsi rating of 50.75 in five-on-five play.

Schultz has been paired with Ian Cole, who has recorded two assists in 18 games, and whose Corsi rating sits slightly under even (48.17). For those who put stock in the stat, Cole is sitting at plus-seven for the playoffs, while Schultz is a plus-three.

Make no mistake, the heavy lifting on defense will be undertaken by the likes of Kris Letang, Brian Dumoulin, Ben Lovejoy and Olli Maatta. But if this third pairing can hold its own in the defensive end while occasionally chipping in offensively, the Penguins might actually start to fly.

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