Rio Fernando will miss Sunday’s Carling Cup final against Aston Villa on Sunday and the friendly against Egypt on Wednesday..
He was scheduled to Rio Fernando return to action on Tuesday night former club West Ham United.
“He tweaked his back in training and he won’t be ready for Sunday,” said Ferguson.
“It is unfortunate for him that he’s going to miss a couple of games.
“Rio has been training great too.
“There have been no mishaps at all. But when you get these twinges you can’t take a chance.”
Hold on there Rio.