Walter Smith fears Rangers could be banned from Europe over the crowd trouble which marred their Champions League game 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 which occurred during Wednesday night's 1-1 Group G draw in Bucharest.

"Obviously, we have received warnings before and it will be hugely disappointing if it does impact on the footballing side of things," he said. "In the current climate, it's the last thing the club needs. European football is important to this club."

UEFA will take Rangers' previous conduct into account when deciding whether to take any action.

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 Smith is worried the next sanction could be even more severe.

He added: "I'm not currently aware of the whole background of the situation. So whether you're critical of the supporters or critical of the policing and the stewards... it is left up to you.

"But it is a situation Rangers have been in before and we can't run away from the fact.

"If it does impact and the consequences mean we do have to miss European games then that would be an enormous blow for the club.

"I have no indication as to what UEFA are proposing but the thing Rangers can't run away from is it's not an isolated incident."