A minute's silence will be held before Ireland's game with Denmark in Copenhagen tonight.
It's after an Irish football fan who'd travelled there for the match was found in the city's harbour.
The 30 year old was discovered in the water at around 10:30am on Sunday, and later pronounced dead in hospital,.
Police are not treating his death as suspicious.
The FAI says the Irish players will wear black armbands to pay tribute to the supporter.
In a statement, the association offered its condolences to the man's family.
"An official request has been submitted to UEFA, by the FAI, to hold a minute’s silence before kick-off in tonight's game in Aarhus", it said.