Nineteen-year-old Renan was sent off for a foul after 45 minutes of Brazil's last-16 clash with Tunisia yesterday, which his side went on to win 4-1.

A statement from the CBF said he was "taunted by the local crowd" after he left the pitch at the Estadio Único Diego Armando Maradona in La Plata.

It said the centre back "responded sportingly" but was then the victim of "several cases" of racism on social media.

"The CBF sent a representation to FIFA in protest of the racist acts suffered by Robert Renan, defender of the Brazilian under-20 national team," the CBF said. 

"The CBF strongly condemns any kind of discriminatory action in football and will no longer tolerate such cases in sport."

In March, Renan received a call up to the senior Brazilian team for a friendly against Morocco, but he has yet to receive a cap.

He signed a five-year deal with Russian club Zenit Saint Petersburg in January, after leaving Brazilian side Corinthians.

The CBF said the social media accounts which had sent racist messages had been reported to FIFA and the "local court", with a request for punishment.

Renan shared Instagram screenshots of racist messages he had received.

It comes after the CBF launched an anti-racism campaign only last weekend, with the message "with racism there is no game". 

Argentina, Brazil's fiercest rival, is hosting the Under-20 World Cup at short notice after Indonesia was stripped of the rights in March following objections to Israel competing.

When asked by insidethegames for comment, FIFA said: "FIFA is currently analysing the reports to assess potential incidents from the match".