Police in Las Vegas have issued a warrant for DNA from Cristiano Ronaldo to assist their investigation into rape allegations, the Wall Street Journal reported.
Ronaldo, the world's highest paid footballer, has been accused of raping a Las Vegas hostess in the city in 2009.
He insists their encounter was consensual.
But Kathryn Mayorga, who was an aspiring model, aged 25 at the time, claims that he forced himself on her in the penthouse of the Palms Place hotel. She reported the assault to police the day after but did not pursue the case, and says she was paid $375,000 to keep quiet about the night.
This autumn the case was re-opened, in the light of the #MeToo movement, and on Thursday it was reported that police in Las Vegas had requested a sample of the Portuguese footballer's DNA.
They reportedly contacted police in Italy, where Ronaldo lives, playing for Juventus following a $92 million transfer from Real Madrid this summer.
The authorities in Nevada are believed to have found DNA belonging to someone other than Miss Mayorga on the dress she was wearing nine years ago. They want to confirm that it belongs to the footballer.
However, given that he has not denied being in the hotel room with her, and indeed was photographed earlier in the evening in intimate conversation with her, it is not clear what the DNA would prove.
Peter Christiansen, Ronaldo's lawyer, said in a statement issued to The Telegraph: "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."
Mr Christiansen has said that he intends to pursue legal action against German magazine Spiegel, after it interviewed Miss Mayorga and published a detailed account of her accusations in September.
"I felt sick and I felt confused," she told the magazine. "And I still had no emotion. No emotion. Through this whole thing ... it took me three months to cry."
Las Vegas police would not confirm the approach.