OGC Nice said their Italian striker Mario Balotelli was the victim of racist abuse during their 3-2 defeat at Dijon in Ligue 1 on Saturday.
"Mario Balotelli got a yellow card... after being annoyed by racist insults from the crowd," Nice said on their official Twitter account.
The alleged incident happened in the second half as Balotelli was talking to referee Baptiste Reynet, pointing his fingers at the crowd.
"I told Mario that I hadn't heard racist insults but he told me that he had," Reynet told French sports daily L'Equipe on Sunday.
"It would have come from two or three spectators."
Dijon coach Olivier Dall'Oglio told L'Equipe: "It is the first time we're hearing this at Gaston Gerard (stadium). There have never been racism problems here.
"If it happened, it is totally inappropriate. But I didn't hear anything."
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