Vegas police have now reopened their investigation into the claims — which include Ronaldo allegedly exposing his penis to the woman in a hot tub, then forcing himself on her in a hotel room.
Ronaldo has vehemently denied the claims
"What they said today: Fake, fake news," the star said on a video posted to Instagram.
"No, no, no, no, no. What they said today? Fake, fake news.
"They want to promote my name. It's normal. They want to be famous to say my name, but it is part of the job. I am happy man and all good."
Las Vegas native Mayorga claimed in an interview with German news magazine Der Spiegel that the football superstar assaulted her in his Palms Casino Resort suite while the two were partying with others.
Ronaldo asked her to join the group in a hot tub, then exposed himself after she went into a bathroom to change, Mayorga told the magazine.
He then asked for a kiss, pulled her on to the bed, and raped her, Mayorga alleges.
Ronaldo's lawyer says they plan to sue Der Spiegel for "moral damages".
In a statement to the BBC, Ronaldo's lawyer Christian Schertz called Der Spiegel's reporting "blatantly illegal" and "probably one of the most serious violations of personal rights in recent years."
Mayorga says she regrets having signed the non-disclosure agreement.
Her lawyer claims Ronaldo admitted the sex was non-consensual in a questionnaire he answered as part of the settlement negotiations in 2010.
Mayorga told Der Spiegel she went to the hospital the next day and reported the incident to police, but her lawyer at the time encouraged her to settle the matter.
Las Vegas cops said they couldn't release the 2009 report because "it's an open investigation".
Meanwhile, Mayorga has gone into hiding. Trolls have already set up fake social media accounts in her name, and Ronaldo's fans are jumping to his defence.
