England boss Fabio Capello says Rio Ferdinand has assured him that he will be fit and ready in time for the World Cup finals next summer, and the Italian, for one, believes the Manchester United defender.

Ferdinand has not played for United or the Three Lions since being given a thoroughly torrid time by Fernando Torres in his side's defeat by Liverpool in October, and is still several weeks from a return to action.

The 31-year-old stopper has had a frustrating year with a persistent back injury and related problems, never able to put in solid stint of games for club or country, nor looking close to capturing his imperious form of old when he has played.

But having been handed a prolongued rehabilitation period out of the game completely in order to thoroughly address his fitness issues, Capello is sure that Ferdinand will return to play a key role for England in South Africa.

The Italian pointed to the example of AC Milan defender Alessandro Nesta - the 33-year-old has been in vintage form for the Rossoneri this season, resulting in calls for him to rethink his international retirement for the finals.

Nesta retired from his Azzurri duties after the last World Cup, deciding that injuries had taken their toll, and Capello asserted that his return to form proves that Ferdinand can come out on the other side of his injury struggles.

"It's too far away to decide about Ferdinand. Look at Italy, Alessandro Nesta was injured for a year, now he's the best and everyone is saying, 'Please come back in the national team'," the Italian told the Daily Mail.

"It's not a worry if Rio is not fit in January because he can be playing in March or April. Rio has told me lots of times that he will be fit."

"I hope he is right because it is really important that the best players will be fit."