Liverpool striker Luis Suarez gave "unreliable" evidence to a panel investigating accusations he racially abused Manchester United defender Patrice Evra, a Football Association report said on Saturday.
The document detailed the reasons for Suarez's eight-match ban, handed out earlier this month for abusing France defender Evra in a 1-1 Premier League draw at Anfield on October 15.
"Mr Suarez's evidence was unreliable in relation to matters of critical importance," the report said, adding "Mr Evra was a credible witness."
The Uruguayan international, the report added, used the word "negro" or "negros" seven times during their confrontation.
Suarez, for his part, has denied the FA charge and has consistently denied he is a racist. The ban was suspended pending an appeal by Liverpool who gave him their full support when the punishment was imposed.
"Mr Suarez's words, which included a reference to Mr Evra's colour, were insulting," said the FA document.
The independent panel took advice from linguistic experts in Latin American Spanish after Suarez said he called Evra "negro in an affectionate and friendly way which was common in Uruguay."
Suarez added he would use the term "negro" when he spoke to black Liverpool team mate Glen Johnson and that he never intended to be racially offensive.
The FA argued that "the conduct of Mr Suarez has damaged the image of English football around the world, given the conduct occurred during the course of one of the most famous games in English football, watched by a huge number of people around the world."
Suarez rejected that argument.
The report said it was important to emphasise that Suarez, whose grandfather was black, had many black friends and the FA did not contend he acted as he did because he was a racist.
Suarez, who was also fined 40,000 pounds over the incident, has until January 13 to lodge an appeal.
Liverpool said Suarez, the club and their legal advisers would take time "to read, digest and properly consider the contents of the judgment and will make no further comment at present."
The 115-page FA report gives a detailed account of the clash between the pair and the evidence given to the three-man panel by both parties and other witnesses.
It concludes: "Mr Evra was a credible witness. He gave his evidence in a calm, composed and clear way. It was, for the most part, consistent, although both he and Mr Suarez were understandably unable to remember every detail of the exchanges.
"Mr Suarez's evidence was unreliable in relation to matters of critical importance. It was, in part, inconsistent with the contemporaneous evidence, especially the video footage.
"For example Mr Suarez said he pinched Mr Evra's skin in an attempt to defuse the situation. He also said his use of the word "negro" to address Mr Evra was conciliatory and friendly. We rejected that evidence," the report added.
"To describe his own behaviour in that way was unsustainable and simply incredible given the players were engaged in an acrimonious argument. That this was put forward by Mr Suarez was surprising and seriously undermined the reliability of his evidence on other matters.
"There were also inconsistencies between his accounts given at different times," said the report.
The confrontation occurred as Evra marked Suarez at a Liverpool corner in the 63rd minute, five minutes after the Uruguayan had fouled the Frenchman.
"In the goalmouth Mr Evra and Mr Suarez spoke to each other in Spanish," said the FA report. "Mr Evra asked Mr Suarez why he had kicked him.
"Mr Suarez replied, 'Porque tu eres negro (because you are black)'.
"Mr Evra then said to Mr Suarez, 'say it to me again, I'm going to punch you'. Mr Suarez replied, 'No hablo con los negros (I don't speak to blacks).'
The report concluded Suarez had said in evidence he would not use the word "negro" on a soccer pitch in England in the future.
"We believe that is his genuine and firm intention," it said.