Benfica midfielder Ruben Amorim will replace Nani in Portugal's World Cup squad, the Portuguese Football Federation (FPF) has confirmed.
The Manchester United winger had missed Saturday's training session by precaution after sustaining a shoulder injury which did not look serious enough to rule him out of the tournament.
However, medical tests undergone this morning to learn the real extent of the problem revealed Nani will not be able to take part in Portugal's World Cup campaign.
An FPF statement read: "Following the injury involving the left clavicle sustained by the player Nani and after monitoring his progress on a daily basis, with the completion of additional tests, we have concluded the competitive inability of the player. The medical file will be presented to the medical department of Manchester United."
The decision comes as a major blow to Portugal's chances in South Africa as Nani, who scored against Cameroon a week ago, had been in scintillating form of late.
Amorim had been on stand-by since Friday, and will board a plane to South Africa still today to join up with the rest of the Seleccao.
The 25-year-old centre midfielder, who can also operate on the right side of the defence and midfield, has been called up for the first time to represent Portugal's main squad, having previously played for the Seleccao's Under-21 and B squads.
Portugal, who find themselves in Group G alongside Brazil, North Korea and Cote d'Ivoire, will kick off their campaign against the Elephants on June 15th.
Can Portugal still go all the way in South Africa? Check out Castrol Football's 2010 FIFA World Cup Success Predictor.
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