A statement from the Portuguese Football Federation read: “After tests we conclude he is unfit to participate in the World Cup.”
“The medical file will now be presented to the medical department of Manchester United.
“In light of the report, the Portuguese Football Federation, taking into account the Fifa regulations for the 2010 World Cup, will call-up Ruben Amorim as a replacement.”
It marks the second Manchester United player to be ruled out of the tournament in South Africa after Rio Ferdinand suffered knee ligament damage last week.
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