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I WAS probably not the only one who was surprised to hear Sir Alex Ferguson saying that Wayne Rooney wants to leave Manchester United – it certainly explains why he has been playing so badly for the last six months.

Obviously it’s been a massive story all week and it has big implications for United as a club – the supporters may have accepted losing Cristiano Ronaldo last year, but Rooney is a different matter altogether.

He is United’s and England’s talisman and, until recently, best player. Everybody assumed he would be at United for life but clearly he has been affected by the year he has off the pitch, and it would be very hard not to be.

Those issues in his private life have started to affect his football though, and when that happens you are in real trouble, even for a player with as much talent as Rooney.

Who will sign him? Certainly not Arsenal, and really only the likes of Manchester City, Chelsea, the two Milan clubs or the Spanish duo Barcelona and Real Madrid can afford him.

Whether any of those clubs will want Rooney in his current state is another matter, but it certainly does not bode well for United, who are struggling for form already, although they are still unbeaten.

Arsenal head to the other side of Manchester this weekend, and face a big test against a City side who are proving that they can live with the pressure up at the top – so far.

Are they good enough to win the title? Time will tell but it doesn’t look like anybody is going to run away with it this season and City will be up there. With the strength they have they have to be considered as title contenders.

The big problem for Roberto Mancini is keeping all of his players happy – he has already lost players such as Craig Bellamy and Stephen Ireland and more will probably follow if they are not getting the games they want. It is a hard juggling act for a manager with so many big-name players.

Emmanuel Adebayor seemed to be angling for a move in the summer, and that will not surprise Arsenal fans given the way he left the Emirates just over a year ago. Of course there is no forgiveness round these parts for the way he celebrated his goal in this game last season.

I am sure he will celebrate again if he gets on the scoresheet again on Sunday, and Arsenal are going to have to play well to come away with a result.

Beating Birmingham was a vital win for Arsenal, especially with Chelsea dropping points at Villa, but now they must get some momentum going and get another result this weekend.