Anti-racism experts say they identified racist abuse and far-right Russian flags at a European Championship match on Friday.
The Football Against Racism in Europe (FARE) network says Czech Republic defender Theodor Gebre Selassie, who is black, was racially abused during Russia's 4-1 win in Wroclaw.
FARE director Piara Powar tells The Associated Press that imperial "Russian Empire" flags were displayed.
UEFA asked FARE to help appoint expert spotters who will report offensive banners, chants and behavior in stadiums.
UEFA has pledged zero tolerance of discrimination at the three-week tournament in Poland and Ukraine.
Film circulating online Saturday also appeared to show some Russia fans attacking stadium stewards in Wroclaw.