Police in Las Vegas have reopened a sexual assault investigation from 2009 at the request of a woman who has alleged she was raped by Cristiano Ronaldo.
Kathryn Mayorga says she was attacked by the Portuguese footballer in a hotel room in the US city that year.
Juventus forward Ronaldo, 33, has dismissed the claim, first reported in Germany's Der Spiegel, as "fake news".
His representatives said he would take legal action against the magazine.
Der Spiegel said Ms Mayorga, 34, filed a report with Las Vegas police shortly after the alleged incident.
In 2010, she reportedly reached an out-of-court settlement with Ronaldo involving a $375,000 (£288,000) payment for agreeing never to go public with the allegations.
Her lawyers are now seeking to declare the non-disclosure agreement void.
Las Vegas police confirmed they had investigated a complaint in June 2009, but added they had no suspect in the case.
"At the time the report was taken, the victim did not provide detectives with the location of the incident or suspect description," a statement said.
"As of September 2018, the case has been reopened and our detectives are following up on information being provided," it added.
Ronaldo joined Italy's Juventus from Real Madrid for £99.2m ($128m) earlier this year.
The Portuguese international is regarded as one of the greatest players of all time.