Real Madrid forward Kylian Mbappe said Benfica's Gianluca Prestianni should be banned from the Champions League after the Argentine was accused of directing a racist slur at Vinicius Jr during the Spanish side's 1-0 playoff first-leg win on Tuesday.
Denying the accusation, Prestianni said the Brazilian misheard him.
The incident occurred shortly after Vinicius had curled Real into the lead five minutes into the second half in Lisbon.
Television footage showed the Argentine winger covering his mouth with his shirt before making a comment that Vinicius and nearby teammates interpreted as a racial slur against the 25-year-old, with referee Francois Letexier halting the match for 11 minutes after activating FIFA's anti-racism protocols.
The footage appeared to show an outraged Mbappe calling Prestianni "a bloody racist" to his face.
The atmosphere grew hostile after play resumed, with Vinicius and Mbappe loudly booed by the home crowd whenever they touched the ball.
"I want to clarify that at no time did I direct racist insults to Vini Jr, who regrettably misunderstood what he thought he heard," Prestianni wrote on his Instagram account.
"I was never racist with anyone and I regret the threats I received from Real Madrid players."
Mbappe told reporters he heard Prestianni direct the same racist remark at Vinicius several times, an allegation also levelled by Real's French midfielder Aurelien Tchouamen.
Mbappe said he had been prepared to leave the pitch but was persuaded by Vinicius to continue playing.
"Sporting matters ceased to be important tonight. This is the Champions League, the most important football competition in the world, and we cannot ignore what happened," Mbappe told reporters.
"We have to set an example for all the children watching us at home. What happened today is the kind of thing we cannot accept because the world is watching us. When someone behaves like this (like Prestianni), we have to speak out and denounce it. I have nothing against Benfica, the club, its fans or its manager. But something has to be done.
"We cannot accept that there is a player in Europe's top football competition who behaves like this. This guy doesn't deserve to play in the Champions League anymore. That's my opinion, but I don't know what they're going to do, I'm not the one who makes these kinds of decisions. UEFA is trying to do things against racism and I think they should do something about what happened here today."
'RACISTS ARE, ABOVE ALL, COWARDS'
When asked whether Prestianni had apologised, Mbappe laughed.
"Of course not!" Mbappe said.
Benfica manager Jose Mourinho said the Argentine had denied the allegations. "Vinicius says one thing and Prestianni says another," Mourinho told Movistar Plus.
Vinicius later posted a statement on social media voicing his frustration.
"Racists are, above all, cowards. They need to cover their mouth with their shirt to show how weak they are. But they have the protection of others who, theoretically, have an obligation to punish them. Nothing that happened today is new in my life or my family's life," Vinicius wrote.
"I received a yellow card for celebrating a goal. I still don't understand why. On the other hand, it was just a poorly executed protocol that served no purpose. I don't like to appear in situations like this, especially after a big win and when the headlines should be about Real Madrid, but it's necessary."
The Brazilian has faced repeated racist abuse in Spain, with 18 legal complaints filed against racist behaviour targeting Vinicius since 2022. The most recent incident was before a Copa del Rey tie against second-tier Albacete in January.