Man Utd defender Rio Ferdinand

Man Utd defender Rio Ferdinand has been ruled out of Sunday's Carling Cup final between Manchester United and Aston Villa and will not be fit to captain England against Egypt at Wembley next week.

The Red Devils defender had been expected to play in the 3-0 win over West Ham after a recent suspension.

However, Sir Alex Ferguson said the 31-year-old felt a problem in his troublesome back on Tuesday morning which now means another spell on the sidelines.

"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."

Aside from missing a major Wembley showpiece, it also looks likely to cost Ferdinand the chance to lead his country into their final friendly before Fabio Capello names his provisional World Cup squad given Ferguson is determined not to take any risks with the former West Ham star.

"Rio has been training great too," said Ferguson.

"There have been no mishaps at all. But when you get these twinges you can't take a chance."