Norwegian assistant referee Ole Hermann Borgan has been stripped of his duties for Wednesday night's Champions League final after being pictured in a Barcelona shirt.
Borgan was photographed by a newspaper in his home country wearing the colours of the finalists, who face Arsenal at the Stade de France in Europe's biggest club match.
While Borgan insists he would have been impartial, UEFA have decided against using him and will replace him with fellow Norwegian Arild Sundet.
Sundet is not yet even in Paris, but will be flown in tomorrow morning to assist referee Terje Hauge, another Norwegian.
UEFA tonight announced: 'The UEFA referees committee has decided that the Norwegian should be substituted by his compatriot Arild Sundet.
'The decision comes after a photograph of Borgan wearing a Barcelona replica shirt was published in his local newspaper.'
Earlier, Norway's refereeing supremo Rune Pedersen told newspaper Drammens Tidende - who printed the picture: 'It was a bit strange of Borgan to pose with one of the final team's shirts ahead of the final tomorrow night.
'It is an unwritten rule that referees should not do anything that can doubt their impartial stance.
'This picture can be brought up beforehand and also after the game, if there are any dubious incidents.'
Arsenal manager Arsene Wenger had earlier laughed off the incident involving Borgan.
Wenger said: 'I never go into a game looking at the referees. I always have a positive feeling about them. They always do the job as well as they can and in an honest way.
'The fact that one of the guys is pictured in a Barcelona shirt doesn't change my mind.'
Referee Hauge was critical, however he recognised why Borgan had acted as he did.
Before UEFA announced his assistant was to be dropped for the game, Hauge said: 'It was a stupid thing to do but I can assure you he did it in pure joy at being picked for this game.
'There was no intention to bring speculation that he is a Barcelona supporter. He put a shirt on to symbolise the final.
'He has never been a Barca fan. It was a stupid slip which he regrets a lot.'
Barcelona boss Frank Rijkaard had been ready to let the match go ahead with the original team of officials in charge.
Dismissing the issue, he had said at Barcelona's press conference: 'Arsenal should give him a shirt straight away and take a photo.'