West Ham United supporters have been banned from travelling to the Europa League game at Rapid Vienna as a result of incidents in their draw with Genk.
European football's governing body Uefa charged the Hammers with crowd disturbances and for their fans throwing items on Cegeka Arena's pitch.
They can appeal and ask for the ban to be suspended until it is heard.
But if they fail it would mean no Hammers fans at their first away game in the Europa League's knockout stage.
The Premier League club have also been fined a total of 34,500 euros (£30,000).