The Pittsburgh Penguins are an all-star team. They’re something you’d create in a video game. They’re all the hockey cards you don’t throw away.

By acquiring Jarome Iginla, Brenden Morrow and Douglas Murray, the Penguins have done more to ruin the trade deadline than the salary cap. They’ve also hurdled to the forefront of the Stanley Cup favorites, what with that spiffy 13-game winning streak sans Evgeni Malkin happening while GM Ray Shero traded peanuts for filet mignon.

But c’mon: The game isn’t played on paper, as the Philadelphia Flyers would tell you for the last 38 years. The Penguins literally look unbeatable now, but they’re not a lock for the Cup.

Here are five reasons why ...

1. Marc-Andre Fleury

The Penguins goaltender has won eight of his last nine starts since March 4, putting together a run that’s seen his GAA drop to 2.24 and his save percentage climb to .918. His 18 wins lead the NHL.

[Also: Jarome Iginla's trade to Penguins an improbable move in today's NHL]

And yet he’s still Marc-Andre Fleury.

Which means you expect those games in which four pucks fly past him, and it’s on the Penguins to make up the deficit. You expect a series like the one he had against the Philadelphia Flyers: a six-game nightmare that saw him give up 26 goals and look systemically flustered. Or you expect the previous Penguins playoff series in 2011, when he gave up 17 goals in seven games to the Tampa Bay Lightning, including 9 in the Penguins’ three straight losses to lose the series.

Battling a neck injury now, Fleury’s never gotten the credit he deserves for the heights the Penguins have achieved. But he’s earned every bit of the suspicion and caution that saddles him as arguably the Penguins’ weakest link.

Are Fleury and Tomas Vokoun good enough this season to lead this team is a Stanley Cup?

Furthermore …

2. The Blueline

Murray is in his Derian Hatcher years: a nasty, formerly elite defensive defenseman who can still bring it physically but whose mobility … well, let’s just say it wouldn’t surprise anyone to see a novice driver learning how to parallel park between two Douglas Murrays.

Kris Letang, Paul Martin, Brooks Orpik, Murray, Matt Niskanen, Deryk Engelland, Robert Bortuzzo and Simon Despres comprise a group that can move the puck and take the body. It’s a solid if unspectacular group, and one that its share of inexperience. There’s no Zdeno Chara here; there may not even be a Duncan Keith.

How you feel about Murray is probably how you feel about this Penguins defense. But while Shero added significantly to the Penguins’ top lines, the backline is less of a sure thing.

Not to say the forwards are a sure thing, mind you.

3. Chemistry

Said GM Ray Shero on bringing Iggy to the ‘Burgh:

“We have a month to sort through the emotions, find some roles for guys, players accepting of those and playing good hockey. The team on paper doesn’t mean too much. We have to do it on the ice. Chemistry for a hockey team is very important.”

One assumes humility will reign in Pittsburgh, with everyone knowing their role and shutting their mouths because the Stanley Cup is the ultimate goal. But that’s a different issue than chemistry, which is something that’s never guaranteed in the NHL when playing matchmaker with stars. Ask the Rangers how Scott Gomez and Jaromir Jagr clicked.

The Penguins are blessed at the moment with arguably the NHL’s hottest line in Sidney Crosby, Pascal Dupuis and Chris Kunitz. Does Iginla have to play with Sid, or is he slotted with Evgeni Malkin and James Neal? Then what does that trickle-down mean for the rest of the forwards? And what does this all mean for special teams chemistry?

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It’s entirely possible that talent clicks with talent, and Iginla recaptures his form from two years ago playing with either center. But there’s always that lingering caution that if ain’t broke, it doesn’t need fixing. And based on the last 13 games, it ain’t broke.

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