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Javier Hernandez Balcazar, aka Chicharito, may be Manchester United's super sub of choice, but goals just aren't enough to prosper at the top of European football.

United look to be lacking inspiration as well as a couple of key signings, and at times it feels as though the Mexican is but a sticking plaster to a wounded team rather than a long-term cure to the club's ailments.

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That is not to say that Chicharito is surplus to requirements or unworthy of wearing the shirt. With his ability to find the net at crucial moments time and time again, he is far from expendable.

However, controlling matches has almost become as important as winning them. The clubs that are able to hog the ball and be proactive when in possession float up to the top of the Champions League pile like the veritable cream of the crop.

While Chicharito's all-round game has shown a dramatic improvement since his arrival in 2010, the striker's link-up play remains his weakest suite.

It's likely the little pea would be a big part of United's first-choice front two if his contributions to the team's build-up moves were as effortless as his resourcefulness in the box.

By contrast, his rather estranged teammate Shinji Kagawa has at times looked to be suffering the very opposite problem. His comfort on the ball and confidence in retaining it in the final third seem not to be enough to counterbalance his lack of a decisive end product.

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Since his arrival last summer, Kagawa has been purported to be the sort of player whom United should build around to establish a new era fit to challenge the dominance of Barcelona's tiki-taka and Bayern Munich's excellence with or without the ball.

In fact, almost immediately after the attacking midfielder signed on the dotted line—fresh from winning the German Player of the Year award with double winners Borussia Dortmund—expectations grew to the point whereby even Sir Alex Ferguson faced fan criticism for not playing the Japan international in the hole, even when his performances didn't justify such special treatment.

Dissent over Kagawa's treatment has only intensified under David Moyes, who was derided by some fans for his strangely detached comments about the playmaker back in September.

"Everyone keeps telling me how good he is so hopefully we'll see that tonight," he told the press, as recounted by Paul Doyle in The Guardian. It was as if he hadn't been paying attention to the player or had yet to see what all the fuss was about when it came to his quality.

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But Kagawa remains an important player to United's vision for the future, if not their present-day first-team selections.

There is no one else like him at the club. Wayne Rooney, who is his main competitor for games in the gap between midfield and attack, is a very different sort of player.

While Rooney likes to rove about from his starting position up front, dropping deep to sniff out the ball before attempting to attack the goal directly or pick out a teammate with a pass from range, Kagawa prefers to ghost into space between opponents' lines.

At Dortmund, he enjoyed success attacking the box with the ball fed into him from behind, running onto a pass to then play in another runner or take a shot himself. His partnership with Ilkay Gundogan, who continually threaded balls through to him, became one of Jurgen Klopp's team's most potent and recognisable attack patterns.

Unfortunately, United suffer in more ways than one because they do not possess an analogue to Gundogan. Tom Cleverley is perhaps the closest player to the German in terms of his mobility and attacking instincts, but he is nowhere near to his level of ability.

As shown by Kagawa's small portfolio of games in which he has prospered for United, he isn't solely reliant on the service of a world-class midfielder to prosper, which is just as well considering the club's recent difficulties in sourcing one.

Last season, he scored a hat-trick against Norwich City. He sought out the space and freedom to lurk outside of the box, acted as a pivot point for United's short passing game and provided a goal threat in his own right.

Against Bayer Leverkusen earlier this year, he again took up the role of a pivot of sorts, remaining fairly static within the left-hand channel, while Robin van Persie, Rooney and Patrice Evra all swirled around him to overload and overwhelm the Bundesliga outfit.

He clearly lacked match sharpness in that game, however, and didn't directly contribute to the 4-2 win in a way that the hype surrounding his talent perhaps suggested he should.

However, while he didn't add any goals or assists, his first touch and tidy passing through tight spaces amplified the activities of those around him and enabled United to shine.

If Norwich offered a glimpse at what Kagawa once did in a Dortmund shirt, then his turn against Leverkusen hinted at the support he can offer to others, especially as a catalyst for fluid, combination play between his position-switching teammates.

United's first game against Real Sociedad in Group A last month should be marked down as another good performance for the Japanese playmaker. Unfortunately, he was again let down by his lack of match practise and the sloppy finishing of those around him.

Yet watching the midfielder indulge himself in his favoured role in the hole behind Rooney was an exciting spectacle. Moyes also enjoyed it, according to his comments, as reported by ESPN FC.

While Chicharito is an excellent goalscorer who is able to provide the finishing touch to a well-worked move or pounce on any half-expected opportunity, Kagawa could alter the team's approach fundamentally.

Deployed in the hole, he could be both a reference point and midfield goalscoring threat, as hinted at by his most positive showings in a United shirt so far. His presence just behind the strikers could allow midfield runners such as Cleverley to compress the space in the middle of the team by playing off the Japanese on his way into the box.

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Roaming out wide, Kagawa can also help to coordinate and create space for Evra's overlaps and cuts inside. He can also spreading the play out to the flanks to play in Adnan Januzaj, Nani and Co.

While United's strikers have begun to find some consistency due to the improved form of the team's wingers and the improved service from out wide, having a player such as Kagawa probing passes into the box and straight to the feet of van Persie would offer another angle of approach.

Fast feet and quick crosses from out wide can bypass a scrabbling defensive line leading to a headed goal or tap in, but against teams that are well-organised and dominant in the air, United can look one-dimensional.

Too often, United are forced to luck out through the sheer individual quality of players such as van Persie, who are often able to magic something out of nothing; however, it is vital to look at creating a more reliable alternative that doesn't always depend on moments of genius.

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As shown by Rooney's movement later in the second half against Fulham, the striker is willing to drop even deeper to vacate space for Kagawa to play in, and it will be interesting to see how that works out on a more regular basis should they play together more often.

Rooney was even more adventurous in his roaming against Leverkusen, and with the Englishman's long-range passing seemingly only improving, allowing him to saunter further back while Kagawa maintains a creative presence just behind van Persie could produce brilliant results.

Pondering the possibilities of how to mesh Chicharito into the team doesn't quite conjure up similarly exciting ideas.

After all, placing him up front as the main No. 9 would mean shifting van Persie into a deeper role, which seems wasteful regardless of his obvious qualities as a No. 10, especially with Kagawa, Januzaj and Rooney on the books.

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Out wide, Chicharito could likely do a job, but it would be a deployment of compromise rather than design.

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Kagawa, on the other hand, for all the frustration he has brought both in terms of being played out of position and his own relative lack of adaptability, is a player who could unlock even greater potential from United's other stars and the on-field relationships between them.

In other words, he's worth the effort even if it'll take time for United to utilise his abilities.

He offers something different and personifies qualities currently missing from the team at large. He bridges the gap between the rapid and technical transitions of Dortmund and the precise, rondo ball retention of Barcelona.

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In United's previous encounters against teams of similar calibre, such as Real Madrid last year and the two Champions League finals against Pep Guardiola's sextuple winners, the club's main assets were too easy to identify and lock down.

Compare such mundane attacking threats to the wholesale approaches of Sir Alex's greatest teams.

The treble winners of 1999 played like a free-flowing force of nature, while the 2008 Champions League and Premier League double winners lacked a primary striker up front. Both sides were unpredictable, multifaceted and difficult to pin down.

That sort of mystique is exactly what Kagawa could offer United once more, which some fans have already caught sight of in the club's flawed prototype performance against Leverkusen this year.

For all his infectious enthusiasm and lethal finishing, Chicharito is a player who fits into systems rather than precipitates them. For that reason, he isn't as pivotal to Moyes and United's future as Kagawa is.