Poland defender Damien Perquis and midfielders Eugen Polanski and Dariusz Dudka could be in doubt for the co-hosts' must win final group match with the Czech Republic after suffering injuries in Tuesday's 1-1 draw with Group A leaders Russia.
"Perquis has a deep cut on his shin. Polanski has a heavily-bruised knee and Dudka has a recurrence of an abdominal strain," team media director and former international Tomasz Rzasa told the Polish news agency PAP.
The three players were to undergo tests later on Wednesday.
"We'll only be able to say more after that," said Rzasa.
Poland have to beat the Czechs to reach the quarter-finals as they have two points while their opponents have three after beating Greece 2-1, also on Tuesday.