Kathryn Mayorga, 34, was unveiled on Friday as the woman who has accused Ronaldo of sexually assaulting her in a Las Vegas hotel room in 2009.
Mayorga's lawyer, Leslie Mark Stovall said in a statement: "The objective of this lawsuit is to hold Cristiano Ronaldo responsible within a civil court of law for the injuries he has caused Kathryn Mayorga and the consequences of those injuries".
Cristiano Ronaldo has branded rape claims against him as "fake news", saying that people "want to promote themselves" by using his name. It's normal. They want to be famous to say my name, but it is part of the job.
"I'm a happy man and all good".
Christian Schertz said in a statement: "It violates the personal rights of our client Cristiano Ronaldo in an exceptionally serious way".
Ronaldo's lawyers say they will sue the German magazine, which originally reported the allegations. Their pictures together went viral around the world at the time and gossip pages tried to figure out her identity. Mayorga's attorney says Ronaldo's team of "fixers" negotiated a $375,000 settlement with her that included a nondisclosure agreement.More news: Manchester City v Brighton - Confirmed Lineups: Pep Guardiola missing star names
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According to her complaint, Ronaldo said he was sorry after the attack and that "he was usually a gentleman", CNN reports. "Then he went down on his knees and said: '99% of me is a good guy, I just don't know about the other 1%'".
Ms Mayorga met the footballer at a nightclub in Las Vegas and accompanied him and a party of guests to his penthouse suite where they were invited to get into a hot...
According to court documents Der Spiegel claims to have seen, Ronaldo insists the sex was consensual. They called the account a "journalistic fiction" that contained "unattributable and unsubstantiated allegations" that were "untruthful and false", according to the lawsuit.
Mayorga did not participate in the article and she was not named in it.
Mayorga told Der Spiegel she no longer felt bound by the non-disclosure agreement as she suffers from the consequences of the night nine years ago.
Those statements mirrored thoughts she once had about Ronaldo, she told the magazine.