Rio Ferdinand (right) hasn't played for England since June 2011.
Alex Livesey/Getty Images

Manchester United manager Alex Ferguson says the club may block Rio Ferdinand's call-up to the England squad because of fears about the defender's fitness.

Ferdinand was recalled by his national side Thursday for the first time in nearly two years and is expected to play in World Cup qualifiers against San Marino and Montenegro.

However, the 34-year-old center back has long-standing fitness issues and Ferguson said Friday that "I need to speak to our doctor ... we prepare Rio in certain ways and he has certain treatments he has to go through.''

Fergsuon says he was "as surprised as anyone'' about the call-up and that Ferdinand "has to make sure he's going to be OK in terms of the number of games he plays.''

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