With news trickling in that Rio Ferdinand might be injured for four months, and it would be longer before one can expect Ferdinand to be fit enough to play again. It raises huge questions for Sir Alex, should he buy another Centre back to cover for Rio or does he have sufficient cover if Evans or Vidic were to be unavailable. There has been a sudden rise in centre backs linked to join United, with Gary Cahill being the latest. So does Sir Alex really need to take a plunge into the transfer market? Rio Ferdinand has along with Vidic formed one of the best central defensive pairings in the world. Their presence at the back is reassuring to any manager as he knows he has two world class centre backs playing for him. But Rio has been plagued with a spate of injuries lately, his availability has been severely limited last season. He made only 21 appearances for United last season, with only 12 of them in the league. His back has been giving him incessant problems over the last two seasons and not healing properly. He missed the World Cup after Emile Heskey landed heavily on his knee, sure to injure any player actually! Well when Rio isn't available, United have Jonny Evans to fill in and Evans has shown that he is more than capable of filling in for Rio without any problems. Backup for Evans would be Wes Brown, John O'Shea, Chris Smalling and Ritchie De Laet, these players are quite good bench players for any team in the World. Wes Brown has been injured a lot off late, but he is decent in the air and is a good header of the ball. He has shown that he is more than capable of playing in the heart of United's defence. John O'Shea, United's utility man can play anywhere in defence, though centre back might not be his best position but he isn't a push over either when he plays there, he's quite capable of doing a good job. Ritchie De Laet is another one who can play at Centre back if needed, very similar to O'Shea in his Versatility, he also provides Sir Alex with cover in the position. Chris Smalling, the most interesting of them all, has shown that he can play at the premiership level, having made 12 league appearances for Fulham last season. Smalling can step in if needed too and should be behind Wes Brown in the Pecking order next season at United. Smalling performed well for Fulham whenever he played. He did however make some mistakes which can be expected from a lad who is only 20. Chris has a bright future ahead and can easily be expected to partner Jonny Evans in future as United's starting Centre Backs. But next season is a good chance for Smalling to show that he can be banked upon to cover the defence in case of injuries or suspensions, and show his real potential to the world. So with so many options available for Sir Alex, it would be unrealistic to expect him to take a plunge into the transfer market for a centre back, unless of course Nemanja Vidic were to leave. But until that happens, the rumours of any central defender joining United will remain just that, a Rumour!

Click on image below to see the Dutch babes at the World Cup