Real Madrid's Cristiano Ronaldo has rejected allegations that he insults Barcelona rival Lionel Messi behind closed doors, instead claiming that he has nothing but respect for his rival.
The pair have been engaged in a battle on the pitch to become the best player in the world with Messi recently beating the Portuguese to equal Raul as Champions League's all-time record goalscorer, while Ronaldo ended Messi's run of three consecutive Ballon d'Or trophies to claim the title last year.
However, a new book claims that, according to his teammates, Ronaldo regularly calls his rival by a vulgar pet name.
In an excerpt from the book "Messi" appearing in the Guardian, Guillem Balague writes: "Ronaldo, perhaps as a symptom of the immaturity that marks so many footballers, thinks it necessary to put on a brave face in front of his team-mates, not be scared of Messi and to rise to the challenge. All very macho; all very false.
"And that is why, according to some Real Madrid players, CR7 has a nickname for him: 'm-----f-----'; and if he sees someone from the club speaking to Leo, he also ends up being baptised 'm-----f-----'."
Ronaldo, however, strenuously denied the allegation in a Facebook post.
"This is absolutely false and I have assured my lawyer takes action to sue those responsible," the Portuguese wrote on Facebook on Wednesday. "I have the utmost respect for all my professional colleagues, and Messi is obviously no exception."