Portugal legend Eusebio was taken to hospital in Poznan yesterday.
The 70-year-old, who scored 41 senior international goals between 1961 and 1973, was with the national team at their Euro 2012 base in Poland when he began to feel ill.
A Federacao Portuguesa de Futebol statement read: "Portugal's football ambassador Eusebio felt indisposed on Saturday when he was at the hotel with the national team in Opalenica.
"After a first observation and contacting his doctor in Lisbon, he went to a hospital in Poznan as a precaution where he is being examined."
Eusebio has been suffering from hypertension recently and has been admitted to hospital three times since December.
