Ashley Cole could miss England's Euro 2012 opener against France on Monday through illness.
The Chelsea defender was absent from a formal reception held for the team in Krakow on Thursday.
Despite Football Association chiefs claiming that the 31-year-old was 'resting', it is feared that he has been struck down with a stomach bug, according to The Mirror.
Everton's Leighton Baines would be expected to replace Cole if he is not fit in time for the match in Donetsk.