Barcelona have confirmed defender Eric Abidal has contracted swine flu and midfielder Yaya Toure has shown symptoms of the virus.
Abidal underwent tests after feeling unwell and developing a fever, and the club doctors diagnosed he is suffering from the disease.
Toure has undergone similar tests after suffering from the same symptoms, but it has yet to be confirmed whether he has swine flu.
"Eric Abidal and Toure Yaya have viral-like symptoms with fever and general discomfort," read a statement on FCBarcelona.cat. "Relevant tests have been carried out on both players.
"In Abidal's case, these tests confirm he is suffering from swine flu.
"As for Toure, during Friday it could be confirmed whether these symptoms are also a result of swine flu.
"Nevertheless, he is certainly sidelined for Saturday's match against Athletic Club.
"The medical services are working following the protocols established by the health department isolating the players, carrying out symptomatic treatment and giving appropriate hygienic measures."
It is a big blow for Barcelona as they have a tough week ahead with a Champions League clash with Inter Milan sandwiched between Primera Liga matches against Athletic Bilbao and second-placed Real Madrid.
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