Cristiano Ronaldo has been urged by lawyers representing Kathryn Mayorga to hand over any evidence to support the claim that documents in a rape allegation were fabricated.
American Mayorga has accused Juventus attacker Ronaldo of sexually assaulting her in a hotel room in Las Vegas in 2009, something the Portuguese has strenuously refuted.
German publication Der Spiegel first reported the claims, which also included the suggestion Ronaldo paid Ms Mayorga $375,000 in 2010 as part of a privacy agreement, preventing her from going public with the allegations. Ms Mayorga filed a lawsuit last month in an attempt to quash that agreement while Las Vegas police have re-opened an investigation.
Ronaldo's lawyer Peter Christiansen confirmed the payment was made to Ms Mayorga, but criticised a fresh report at the weekend which he says was based on doctored evidence.
But a statement from lawyers, Larissa Drohobyczer and Leslie Stovall, representing Ms Mayorga, said: "We thank Cristiano Ronaldo's latest lawyer for confirming and admitting in his October 10, 2018 statement that the 'Football Leaks' documents were obtained from Cristiano Ronaldo or individuals acting on his behalf.
"We look forward to reviewing any evidence that tends to prove, as Mr Ronaldo's lawyer asserts, that some of the 'Football Leaks' documents were altered, fabricated, or contain false/inaccurate information.
"In both civil and criminal cases, disputes regarding the accuracy of documents are generally questions of fact to be decided by the jury. A jury determines the accuracy of disputed documents by: 1) Comparing of the different versions of the disputed documents; 2) Listening to the testimony of the individuals who wrote, prepared, transmitted, and stored the disputed documents; 3) Considering the circumstances under which the documents were written, prepared, transmitted, stored and maintained; and 4) Listening to the testimony of forensic experts who have examined the disputed documents, and the devices upon which the documents were written, prepared, transmitted, and stored.
"In a civil case, discovery is conducted to obtain evidence regarding these matters through the exchange of disputed documents, the forensic examination of disputed documents and devices, and the examination of witnesses under oath. In criminal cases, the prosecutors rely upon investigator's review of disputed documents, the forensic examination of devices and disputed documents, and questioning of witnesses.
"Any document or information under the control or in the possession of Cristiano Ronaldo should be immediately turned over to the appropriate law enforcement agencies and the offices of Stovall & Associates to expedite the investigation and resolution of the alleged discrepancies in the 'Football Leaks' documents."
In a statement earlier this week, Christiansen had said: "The documents which purportedly contain statements by Mr Ronaldo and have been reported in the media are complete fabrications. It is my understanding that in 2015, dozens of entities [including law firms] across many different industries throughout Europe were hacked and their electronic data was stolen and captured by a cyber-criminal.
"This hacker attempted to sell this data, and one media outlet has now irresponsibly published the stolen documents, significant portions of which were altered and/or completely fabricated. To absolve any doubt, Mr Ronaldo has always maintained, as he does today, that what occurred in 2009 in Las Vegas was consensual in nature.
"While Mr Ronaldo does not deny the existence of the mutual agreement and release, his motivations for agreeing to that resolution have been twisted to say the least.
"Far from any admission of guilt or any ulterior motive, Mr Ronaldo was advised to privately resolve the allegations against him in order to avoid the inevitable attempts that are now being made to destroy a reputation that has been built upon hard work, athleticism and honour.
"Unfortunately, he now finds himself embroiled in the type of litigation that is all too commonplace in America."
Christiansen's statement went on to stress Ronaldo's innocence while again strongly criticising the reporting of the allegations facing the Portugal captain.
"While Mr Ronaldo is accustomed to being the subject of press attention that goes along with being famous, it is absolutely deplorable that any media outlet would support or advance such an elaborate and deliberate defamation campaign based on stolen, easily manipulated digital documents," the statement continued.
"Mr Ronaldo will leave future discussion of any and all legal matters to his attorneys here [in Las Vegas] and in Europe. He is confident that the truth will survive this frenzy and the laws of Nevada will be upheld and enforced."
Meanwhile, on Thursday, Real Madrid announced they are to take legal action against a Portuguese newspaper that suggested the club pressurised Ronaldo into seeking a non-disclosure agreement (NDA) with Mayorga.
Correio da Manha claimed on Wednesday that the NDA was put in place at Madrid's request, with the club having spent a then-world-record fee to sign the forward from Manchester United just weeks after the incident is claimed to have taken place.
Madrid insist that is "false information" and, in a statement, said: "Real Madrid CF can today announce that the club has taken legal action against the Portuguese newspaper Correio da Manha for publishing categorically false information in an effort to seriously damage the image of this club.
"Real Madrid has absolutely no knowledge of any of the information that the newspaper published with regard to the player Cristiano Ronaldo, and therefore the club was unable to take action on a matter of which it had no knowledge.