Ronaldo has “vehemently” denied the rape allegation, saying he had “consensual” relations with his accuser.
The Portuguese football star has previously denied raping American woman Kathryn Mayorga in June 2009 in a Las Vegas hotel room after she made the claim 10 days ago.
In a new statement from his lawyer in the US, he admitted for the first time to having relations with Ms Mayorga, but that it was “consensual in nature”.
Peter Christiansen issued a statement in which he does not deny Ronaldo and Ms Mayorga reached a non-disclosure agreement (NDA) in 2010.
But it declares documents cited in media reports about the athlete’s encounter in 2009 were altered before being “irresponsibly published”.
A lawsuit filed on September 27 in Nevada state court seeks to void the NDA that Ms Mayorga’s lawyers say she signed while accepting $375,000 (£284,000) to keep quiet.