The referee who booked Mario Balotelli after the Nice striker alleged he had been the victim of racist abuse has insisted he did not hear the insults.
Nicolas Rainville showed Balotelli a yellow card after the forward gestured to the crowd during Nice's 3-2 league defeat at Dijon last Saturday.
Balotelli said he had been the target of monkey chants from home fans, and the Disciplinary Commission of the French Football League (LFP) will open an investigation into the matter when it sits on Thursday.
In a news release issued by the Elite Football Referees' Syndicate (SAFE), Rainville said he "did not hear insults or shouts coming from the stand."
"If I had heard monkey chants as indicated in the request from OGC Nice, I would never have given Mr. Mario Balotelli a booking," Rainville said. "I can understand such a reaction from a player affected by those sorts of insults."
Two associations, SOS Racisme and Sportitude France, have launched an appeal for witnesses to come forward.
The Representative Council of Black Associations (CRAN) has made an official complaint to police about Rainville, whom they claim is "complicit" in racism by failing to act against the alleged perpetrators and punishing Balotelli.
"This complaint has no basis. It's ridiculous and scandalous," France's technical director of refereeing, Pascal Garibian, told L'Equipe, and backed Rainville by stating that "at no time" had the match official acted wrongly.
"From a human perspective, as far as the CRAN are concerned, it's irresponsible to throw a man to the wolves on the pretext there is media coverage. Nicolas has been hurt by that.
"In the mail addressed to the LFP by Nice to ask for the yellow card for Mario Balotelli to be rescinded, the player and the club have emphasised the referee's very good behaviour on a human level vis-a-vis the player.
"This complaint is scandalous because it gives the idea the referee is complicit when the facts show the opposite of what the CRAN is complaining about."
Garibian said that Rainville had booked Balotelli because his gestures towards the fans "were similar to the attitude of a Nice player who had, a few minutes earlier, celebrated a goal in a manner that could be deemed provocative."
The Nice player, Alassane Plea, had stood in front of a stand full of Dijon fans and put his fingers in his ears.
"Following on from that, Nicolas Rainville gave Mario Balotelli a booking," Garibian said. "But if he had heard such insults, he would never have booked him. The referees fight against all racist behaviours."