Arsenal are to report Real Madrid to Fifa over the Patrick Vieira saga. The France midfielder decided to stay with the Gunners last week after he had looked set to join the Spanish giants.
Arsenal initially said they had no problem with the way Real had behaved but vice-chairman David Dein has now said: "Patrick's head was turned.
"He was compliant but it's against Fifa rules to destabilise a player under contract. We will complain because rules are there to be respected."
Vieira, 28, told Dein and Gunners boss Arsene Wenger on Thursday night that he had changed his mind.
"He told Arsene and me in early June that he wanted to leave and go to Real Madrid," Dein revealed.
"We obviously tried very hard to dissuade him, but his mind was very made up.
"We came within hours of losing him, maybe just an hour. Literally, just prior to signing off an agreement, he said 'I cannot leave the club'."
Meanwhile, Real coach Jose Antonio Camacho says their failure to sign Vieira is a blow to their hopes for next season.
"Vieira would have given us different power in the middle of the park," he told Spanish newspaper Diario AS.
"He is a sensational winner of the ball, especially in the air from goal kicks and he also has great strength.
"Maybe Madrid will not now be as good as our opponents in that aspect and that is where we will have to improve."