Only hours after the president of European soccer’s governing body urged referees on Tuesday to call a halt to games marred by racial abuse, the Juventus striker Moise Kean, who is black, was subjected to racist abuse by fans. He was then criticized by one of his own teammates, as well as his manager, who blamed him for provoking the taunts.

The insults directed at Kean — and the reproach from his teammate and his coach — came only hours after Aleksander Ceferin, the president of UEFA, European soccer’s governing body, had told an equality conference in London that his organization would speak with referees and encourage them “not to be afraid to act” if they heard racist abuse from the crowd.

Hours later, in a match in Italy’s Serie A at Cagliari, Kean, a 19-year-old Italian forward of Ivorian descent, and two other black teammates, the French midfielder Blaise Matuidi and the Brazilian defender Alex Sandro, were subjected to consistent racial abuse from Cagliari fans during Juventus’s 2-0 victory.