The Spanish Football Federation (RFEF) has offered its "total and unconditional support" to a referee accused of negligence by Real Madrid for failing to report insulting chants aimed at Vinícius Júnior.

Referee Juan Martinez Munuera did not include chants from the crowd of "Vinícius, die" in his official match report after Madrid's 4-2 win over Osasuna at El Sadar on Saturday, in which the Brazil forward scored twice.

On Monday, Madrid filed a formal complaint with the RFEF, saying the official had "voluntarily and deliberately omitted the insults and humiliating chants ... despite being warned insistently by our players at the same time that they were occurring."

The federation responded with its own statement on Tuesday.

"The RFEF's Technical Committee of Referees wants to express its total and unconditional support for the First Division referee Mr. Juan Martinez Munuera, after the unfair accusations made by Real Madrid in its complaint to the Competition Committee," it said.

"The aforementioned club alludes to a series of warnings made by its players about shouts or chanting by the public ... We must clarify that, once the match audios had been reviewed, no indication of any Real Madrid player on this issue could be heard, and nor did the club's delegate inform the referee of any incident after the match.

"The referee can only include in his report those incidents which occurred before, during and after the match on the field of play ... However, Real Madrid is unaware that the official match reporter, who is part of the Technical Committee of Referees, did reflect those crowd incidents which he considered significant in his report ... These reports are sent to the disciplinary body of the RFEF at the end of each day, as has been done for several seasons."

Osasuna also issued a statement on Tuesday, denying that any racist chanting had taken place and condemning the insults "by a minority" of fans.

Real Madrid have also reported chants of "Vinícius, die" before Barcelona's Champions League round-of-16 tie with Napoli and chants of "Vinicius, chimpanzee" ahead of Atletico Madrid's game with Inter Milan last week to hate crime prosecutors.