Charlton's chairman has lodged a complaint to UEFA after being injured by police in Madrid last month.
Michael Slater was knocked unconscious before the Champions League clash between Real Madrid and Manchester City.
Slater, a Manchester City fan, suffered minor head injuries and severe bruising after being caught up in an incident when police wielding batons allegedly charged City supporters in an unprovoked attack prior to kick-off.
Slater told Charlton's official website: "I can confirm that I was assaulted by at least one police officer in Spain without any provocation at all.
"I have been in contact with the FA, and I am expecting them to take the matter up formally with UEFA."
City lost 3-2 to Madrid in the Champions League clash on Tuesday 18 September.