It always seems to be a bad move to break up one of the best lines in hockey.

However, with the return of Sidney Crosby to his full-time day job, the highly-successful line of Evgeni Malkin, James Neal, and Chris Kunitz likely will be split up – that is, if you believe what Dan Bylsma has said on the issue.

In breaking up that unit, Bylsma’s hope is to rekindle the torrid pace of production from a line featuring Crosby, Kunitz, and Pascal Dupuis during the 2010-11 season before Crosby was sidelined with concussion and neck issues.

But with Kunitz gone from the Malkin line, a void has been created, and it’s not one that can be filled with just any player. While Malkin and Neal are highly-talented and creative players, they need space to work their magic. Kunitz not only created that space, but also was capable of contributing to their offensive production, while covering for them defensively at times with his speed and tenacity.

As we mull over the possible replacements, many names are beginning to emerge, with Tyler Kennedy, Matt Cooke, Eric Tangradi, and Beau Bennett being the most common.

So let’s examine.

Kennedy is a speedy, tenacious forechecker when on his game. While he doesn’t have a big frame, he is an effective hitter and board worker. He also has demonstrated an ability to produce offense and score goals. That said, Kennedy also has a knack for killing plays by holding on to the puck too long and taking ill-timed low percentage shots. And, while he has been a staple on one of the best third lines in hockey for years, he’s not particularly adept at defense.

Result: If he’s at his peak, he would be a strong fit. But years of watching Kennedy have shown that he’s often off his peak and is better suited for a third line role where he can stick to grinding it out with his more defense-oriented linemates.

Cooke spent some time last year skating with Crosby and displayed an unexpected ability to support his much more skilled linemate. As one of the league’s most prevelant hitters, Cooke doesn’t shy from contact, often engaging his opponents in it, and he certainly doesn’t avoid getting dirty along the boards. Age and a slowing set of wheels are catching up with Cooke, and a reputation of being the game’s dirtiest player (despite a transformation last season), could cause issues when skating increased minutes with two of the game’s best forwards.

Result: It’s no secret Cooke is a feisty, hard-hitting forward, but what many tend to overlook is his quality work in his own end. If he can bring this on a consistent basis, game in and game out – and there’s no reason to believe he can’t or won’t – Cooke, a less-skilled Kunitz, would be the ideal internal winger option for Malkin and Neal.

Tangradi is a polarizing figure. He’s a young player who “hasn’t gotten a chance,” but he also hasn’t earned his chance. While his offensive numbers (at least in the goals department), have been semi-impressive this season, he remains a question mark in many areas. In the past, he’s shown an aversion to initiating physical contact, despite his big frame. He also has a long way to go to prove himself defensively. But, at 23, the confidence boost he would get from such an important role could be precisely what he needs to jump start his career.

Result: Is he fast enough, does he think the game at a high enough level, can he contribute defensively, is he willing to get dirty along the boards and in front of the net? These question marks make selecting him as an option difficult. On one hand, his big body would make that line quite imposing. On the other hand, imposing means nothing if it isn’t supported physically. I think Tangradi is ready for the NHL, but he seems like a better replacement on the third line if Cooke or Kennedy gets a promotion.

Bennett is the wildcard here. The highly-skilled, speedy winger isn’t cut from the same cloth as Kunitz. In fact, they’re completely different fabrics. About the only things the two wingers have in common is that they are fast and can contribute offensively. Bennett would have no problem keeping up with the foot speed of Malkin and Neal, and he certainly could feed them the puck. But as a first-year professional, Bennett might not think the game at a high enough level just yet to be handed such an important role.

Result: Bennett’s small frame makes it difficult for him to get dirty in the corners, and his lack of defensive awareness could make him a liability on such a gifted line. Quite honestly, he wouldn’t be creating space for Malkin and Neal, but rather making things more crowded for them. Give him a year and he’ll be in Pittsburgh flanking the wing of one of the Penguins’ star centers. But for now, he needs to work on expanding his game.

Of course, the Penguins also could look at external options, with names like Mike Knuble (free agent) and Ryan Malone (signed with Tampa Bay) floating around the rumor mill.

While Knuble, at an affordable price, might be worth the gamble, he doesn’t bring what the team needs. As for Malone, he has three years (including this year) left on a contract paying him $4.5 million per season. He’s a potential buyout victim for this summer, at which point he might be a much more attractive option for the Penguins.

So, with all that said, who do you think should get the final spot on the scoring lines, flanking Malkin and Neal?