Ally McCoist is not sure Rangers can do any more to prevent "mindless idiots" marring future Champions League matches following this week's crowd trouble against Unirea Urziceni.
The Ibrox club, who have been charged with the improper conduct of their supporters, will discover on Thursday whether they will be punished for the ugly scenes that occurred during Wednesday night's 1-1 Group G draw in Bucharest.
Assistant manager McCoist told BBC Scotland: "Ourselves, like many other clubs, have mindless idiots who bring shame on the club. The club's doing just about everything possible to deal with these idiots but I don't know if we can do any more."
Television pictures showed a number of travelling fans clashing with Romanian police in the stands during half-time of Wednesday's match, while one supporter was seen to rip out a seat.
Police used CS gas spray in an effort to disperse fans.
Although condemning the minority of fans involved, chief executive Martin Bain insists it was triggered by poor organisation at the Steaua Stadium and over-zealous policing.
He has vowed to argue a strong case in front of UEFA's control and disciplinary body next week.
Bain's explanation was also backed by Superintendent Mike Dean of Strathclyde Police, who was helping to co-ordinate security at the ground on the night.
UEFA appear to have taken this into account after beginning disciplinary proceedings against Unirea on Friday over a "lack of organisation" regarding the entry procedure for spectators at the ground.
But Rangers' previous conduct will also be considered when the control and disciplinary body meet next week. The club have been fined twice in the last four seasons by European football's governing body over the behaviour of their fans, and manager Walter Smith fears the next punishment could be a ban.
