Antonio Rüdiger alleged that he was racially abused in the final moments of Real Madrid's 3-1 win over Pachuca in the Club World Cup on Sunday, and manager Xabi Alonso said that FIFA has launched an investigation.
Referee Ramon Abatti crossed his forearms in front of his chest, which signals the activation of the anti-racism protocol, five minutes into stoppage time after a brief scuffle erupted following a foul on Germany international Rüdiger.
Asked if Rüdiger had been the victim of racism during the game, Alonso told a news conference: "That's what Rüdiger said, and we believe him.
"It is important to have zero tolerance in these kinds of situations. FIFA now is investigating. That's all I can say."
It was not immediately clear whether the alleged abuse came from the crowd or an opponent. Gustavo Cabral, the Pachuca defender who Rüdiger clashed with before he spoke to the referee, has denied that he racially abused the Madrid defender.
"There was nothing racist. I called him 'chickens---' as we say in Argentina, that's it," Cabral told reporters in Spanish after the game.
FIFA was not immediately in a position to clarify the incident when contacted by Reuters, as it still awaits the referee's report.
Rüdiger, 32, has been the target of racist abuse several times when playing for Chelsea, AS Roma and Madrid, both on the pitch and online.
Information from Alex Kirkland contributed to this report.
