The Wall Street Journal claims that authorities in Nevada recently sent the warrant to Italy, where Ronaldo now plays for Juventus.
The Independent has contacted the Las Vegas Police Department (LVPD) and the Italian authorities for comment but neither party had responded at the time of publication.
“Mr. Ronaldo has always maintained, as he does today, that what occurred in Las Vegas in 2009 was consensual in nature, so it is not surprising that DNA would be present, nor that the police would make this very standard request as part of their investigation,” one of Ronaldo’s lawyers, Peter S. Christiansen, said in a statement on Thursday evening.
Juventus declined to comment.
Las Vegas police had reopened their investigation into the 2009 incident after Ms Mayorga filed a lawsuit last year alleging that Ronaldo had raped her in a hotel room and then paid her $375,000 to keep it secret.
German publisher Der Spiegel carried legal documents, obtained by Football Leaks, detailing the serious allegations against Ronaldo, now 33, who has consistently and emphatically denied all wrongdoing.
“Keen as I may be to clear my name, I refuse to feed the media spectacle created by people seeking to promote themselves at my expense," he said in October.
“My clear conscious [sic] will thereby allow me to await with tranquillity the results of any and all investigations.”
The warrant for a DNA sample is the first time it has become public that the LVPD have reached out to Ronaldo since reopening their investigation.
"Ronaldo has leverage in terms of cooperation [with the police] because he cannot be compelled to appear in Las Vegas at this point,” Michael McCann, an associate dean at the University of New Hampshire School of Law and legal analyst for Sports Illustrated, told The Independent.
“If he cooperates he might only agree to do so by video conference and by answering questions in writing. He might also be willing to share electronic evidence.
“If he doesn’t cooperate, the police could take a negative inference from his lack of cooperation,” he adds. “That doesn’t mean he would be charged with a crime, but lack of cooperation can make law enforcement more suspicious about a person."
Ronaldo has vowed to clear his name, while Juventus have backed their £90m signing and Real Madrid are suing a Portuguese newspaper that claimed they forced Ronaldo into paying off Mayorga while he was a player at the Bernabeu.
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