The Football Association are calling for Aston Villa to ban for life the supporter who struck referee's assistant Phil Sharp with a coin during Saturday's Premier League clash with Portsmouth.
Sharp was hit on the forehead by a 50p coin thrown from behind the Villa Park dug-out towards the end of the goalless draw and needed treatment for a substantial cut before being able to complete the game.
The FA pledged to investigate the matter within half-an-hour of the final whistle and clearly expect Villa to take a tough stance if the culprit is identified.
FA spokesman Andrin Cooper said: "These sort of incidents are absolutely unacceptable. There is no way that match officials should have to worry about their safety at the game.
"There is no place for this sort of behaviour and we will be fully investigating this matter in co-operation with Aston Villa and the police.
"We would fully expect that, if the individual is identified, he would be banned for life.''
Villa have reiterated their determination to find who was responsible for the incident and are working closely with the police on the matter.
Club spokesman Steve Tudgay said: "The police and the club are holding a joint investigation. CCTV footage of where the incident occurred will be checked.
"The culprits will be dealt with by the police but, from a club point of view, any culprit will be banned for life. We condemn such actions in the strongest possible terms.''
Pompey manager Harry Redknapp admits to being appalled in general by some of the behaviour from rival supporters he witnesses in and around football grounds.
He said: "Hopefully they will catch who was responsible for this particular incident on the cameras and ban him from life in football. They've got no place in our marvellous game.
"I did looked around and there was a guy making filthy gestures, shouting obscenities and there were kids there. I just pointed at him.
"I don't know whether it was him who threw the coin - but his language and, what he was doing in front of young kids, was a disgrace anyway. He's got no place in football.
"I was sorry for the linesman who ended up with a nasty gash on his head and I'm sorry for the game when we have people like that.
"You come out of football grounds now and you see grandparents with kids and they are sticking fingers up at you and they are making filthy gestures to the team coach.
"You look at them and these people and it scares me. I think it is horrific, I really do.''
Villa boss Martin O'Neill said: "What happened, is totally unacceptable. There is no place for it in the game.
"The fourth official had put up four minutes of extra time and the next minute the young linesman has gone down. He has been hit on the head.
"He was obviously shocked and, whether he is fine or not, that could have been very serious indeed. There is absolutely no place for that whatsoever.
"It is particularly disappointing for us because certainly the chairman (Randy Lerner) has made great strides here. The club is supporter-friendly, trying to get people into the ground to support us.
"That is really disappointing and I am sure I would echo his thoughts. It was mindless.
"In the main, the clubs are well stewarded. I don't think you can legislate for something like that. It is against the law.
"We all make an effort but that is an incident that could have happened on any ground whether well stewarded or not.''