Osasuna have denied allegations of racist chanting by their fans during last weekend's 4-2 home defeat against Real Madrid, according to their Tuesday statement.
Real Madrid have filed a complaint against the referee who officiated Saturday's match at El Sadar Stadium.
They claim that the referee did not include in his match report the alleged insults directed at their Brazilian forward, Vinicius Jr., and the capital club announced this on Monday.
"After the information published in the media following Real Madrid's press release, which portrays El Sadar with racist behavior, Osasuna wants to clarify that no racist chants were heard during Saturday's match," Osasuna said.
"The club will not tolerate any damage to the reputation of the Osasuna fans, who, throughout their history, have been known for their anti-racist stance."
Osasuna admitted that a small number of their fans insulted Real players and condemned the behavior.
"Additionally, Osasuna wants to express its rejection of the insults – which did not have racist references – that a minority directed last Saturday at El Sadar," they added.
"The club rejects these chants that, unfortunately, its players also have to endure when they visit other LaLiga stadiums."
The RFEF's Technical Committee of Referees (CTA) backed the match official and said Real Madrid's accusations were "unfair."
"(CTA) wants to express its total and unconditional support for the First Division referee Mr. Juan Martinez Munuera, following the unfair accusations made by Real Madrid CF in their complaint to the Competition Committee," the CTA said on Tuesday.
"The aforementioned club refers to a series of warnings made by its players about shouts or chants from the public against their player number seven.
"We must clarify that, after reviewing the match audios, no indication was heard from any Real Madrid CF player regarding this issue, nor did the club delegate inform the referee of any incident related to these shouts or chants after the match."
Reuters contacted Real for comment on the CTA statement.
The Committee also stated that the referee did include in his report the incidents that he deemed significant, "fulfilling his duties ... in the fight against violence, racism, and xenophobia."
A reference to abusive chants aimed at Vinicius in the first half of the match was included in a separate incident report compiled by the CTA, a copy of which was attached to the CTA's statement.