Manchester derby will be United's biggest test of the season so far

The selection for Saturday's home game against Wolves showed how threadbare United is, as the lineup featured two left backs and Park Ji-sung playing as a central forward. With a virus sweeping through the squad, it could be even thinner by kickoff at Eastlands. On Saturday, the sixth-minute injury to Owen Hargreaves, heartbreaking as it must have been for him after more than two years without a start, almost seemed to do United a favor, allowing the introduction of Bebe alongside Javier Hernandez up front, with Park dropping into midfield, from where he scored his two goals.

The South Korean's season has been as unfathomable as anybody's. Until he scored against Wolves in the League Cup, showing poise and precision in the box that defied his reputation for squandering chances, he had been rather neglected, despite United's problems. He was then excellent in the 2-0 win over Tottenham, and is likely to have a key role in the Manchester derby.

United has favored an old-school 4-4-2 this season, an oddity given the tribulations Ferguson went through trying to adapt to a single-striker system in the early part of the decade, and probably another indication of how his resources have been reduced. He has, in truth, little option, at least until Wayne Rooney returns to fitness and form. The brightest aspect of this season by far for United has been Javier Hernandez, the lively and inventive Mexico forward. Michael Owen, who has become startlingly clearsighted since accepting his career is as good as over, says he can see the similarities between Hernandez and himself at a similar age. There are differences -- Hernandez is not as quick as Owen was, but probably has a better all-around game -- but like Owen, Hernandez needs a strike partner, presumably Dimitar Berbatov.

Berbatov, as a composite player who is capable of holding the ball up and feeding through-balls, is ideal in that regard and he has shown in flashes this season the level of football of which he is capable. He will not, though, go tearing back into midfield to regain possession, which leaves United worryingly light against City's formidable midfield trio.

Nigel De Jong, Gareth Barry and Yaya Toure have been the best ball-winning unit this season, eventually grinding down even Chelsea. United, with only two central midfielders, would see that as a danger area anyway, but that's particularly so because it doesn't have a central player anywhere near as robust as any of City's three. Darren Fletcher, who has emerged as one of United's key players over the past couple of seasons after coming through a period of decision, can match them for energy but may be outmuscled. Paul Scholes is showing increasing signs of age and, although he is still more than capable of conjuring a match-winning performance, the recklessness of his tackling must be a concern, which has only become more prevalent as his pace has declined, particularly in the fevered atmosphere of a derby.

With Nani (assuming he recovers from a groin injury) deployed on the right as the link between midfield and attack, and the one real sparkle in a largely prosaic side, that gives Park a vital task on the left. He will tuck in, becoming an auxiliary central midfielder, but he must also offer support to left back Patrice Evra, both in dealing with the right wing -- presumably David Silva, although it could be Adam Johnson -- and in offering an attacking thrust. City's two fullbacks aren't particularly adventurous, and right back Jerome Boateng is likely to remain reasonably deep, but he still can't be allowed to become effectively a free man. The more work he has to do on his flank, the less he can support his two central defenders in dealing with United's two strikers.

Ferguson's one option in trying to address that inferiority in midfield is to match City shape for shape, playing Park and Nani high up the field and leaving out Hernandez for an additional central midfielder, probably Michael Carrick. That is more likely to be an alternative if things are going badly, though, not least because even matching three-on-three, City seems to have the edge -- physically, at least -- in that area. By almost surrendering the center, United can at least try to cause City problems in other areas.

In that regard, United's approach becomes almost like guerrilla warfare: leave Fletcher and Scholes deep to protect the back four and hope City's relative lack of finesse means it is unable to break through, while looking to do sufficient damage in isolated raids to take something from the game. That plays on City's major weakness this season, which has not been winning the ball, but doing something worthwhile with it.

Without attacking fullbacks, and with a midfield trio lacking a playmaker -- Toure and Barry may have license to push forward, but neither is exactly visionary or subtle in his play -- City can at times become a broken team, with seven defensive players, three forwards and little in-between. That is why Carlos Tevez is so vital to the system, a classic false nine who drops off to link the two parts of the team together. Since Roberto Mancini took over last Christmas, Tevez has played at least a half in 34 games. Of those matches, City has won 21 and lost eight. Without him, City has lost four and drawn four out of 11, a statistic made even more striking when considering the fact that two of the three wins it managed without Tevez were home Europa League games.

As Tevez drops deep, he creates space for City's two wide forwards to cut in and exploit, as Mario Balotelli did in scoring twice in Sunday's 2-0 victory against West Brom. But the Italian is suspended after being sent off Sunday, robbing City of its most explosive attacking force. James Milner is the likely replacement, and his battle with John O'Shea, assuming he gets the nod over Rafael at right back, is likely to be a slog. The key attacking battle will be on the other flank, between Evra and either Johnson or Silva.

Given the personnel and given the systems, it's hard to believe City will not dominate the center. The issue then is whether City has the invention to make the most of it, and whether the potency of United's front two outweighs the fact that Ferguson's club is likely to be on the back foot for most of the game.