These are troubling times for anyone associated with Manchester United, as well as the lacklustre performances, there are greater concerns about the long-term stability of the club as the true extent of their crippling debts becomes clearer. Nobody outside the club is really quite sure of how much of the Cristiano Ronaldo fee is available to Sir Alex Ferguson and how much of it went to servicing the debt. The decision to not seek a replacement has left the squad lacking that extra bit of magic and it's a testament to the managerial skills of Ferguson that his side are still in with a chance of winning 3 trophies considering how they have played so far this season. A growing concern for fans of the club is the position of Wayne Rooney; he is the club’s most valuable player and though his commitment to United cannot be doubted, is there a chance that he could be sold?

Rooney has no desire to leave United and has made it clear that he would be happy to see out his career at Old Trafford. As it is, his value is such that there are very few clubs that could even think about putting a bid in for the England striker. But there are a couple of sides who will have one eye on the state of affairs at United. The two cash-rich sides of the moment are City and Real Madrid.

In recent years Real Madrid have begin treating Manchester United as a feeder club; from Beckham to van Nistelrooy and then Ronaldo. Nemanja Vidic is thought to be next on their hit-list but the club is also thought to be keen on Rooney as a replacement for Raul, and Ronaldo has said that he would love it if his former United colleague were to join him at the Bernabeu.

It would be crazy for United to sell Rooney given that all their attacking play goes through him now; the form of Berbatov has meant that Rooney has had to shoulder the responsibility of scoring goals. He is in great form this season despite having to play as a lone striker at times. But irrespective of the bond between the player and the club; you have to wonder if United are in a position to reject a massive bid from either Real Madrid or Manchester City. Rooney is one of the world’s best and as a starting figure his value in the current market would be around £40million, but both Real Madrid and City have shown that they would be willing to pay much higher fees to get the players they want; City were willing to pay £100million for Kaka.

In the same way that Liverpool would be forced to think about an astronomical bid for Torres if it came in; United would certainly have to consider a bid for Rooney if it was high enough, such is their precarious financial situation. This should be a real concern for United fans as without Rooney, the current United side begins to look very average and if he was sold; there is no guarantee that the manager would be able to use all of the fee to replenish his squad.

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