Liverpool striker Luis Suarez was accused of giving "unreliable" and "inconsistent" evidence during the hearing which led to his ban for racially abusing Patrice Evra, it was revealed on Saturday.
In a detailed 115-page ruling released by the English Football Association, the panel found that elements of Suarez's testimony in the case had been "incredible" given the ill-tempered nature of his exchanges with Evra.
The judgement revealed that Suarez had called Manchester United defender Evra a "negro" no fewer than seven times during the match at Anfield on October 15.
According to the panel, when Evra asked Suarez why the Uruguayan striker had kicked him, he replied "Porque tu eres negro (because you are black)."
When Evra warned him he would punch him if he repeated the remark, Suarez is alleged to have responded "No hablo con los negros (I don't speak to blacks)."
Suarez, who was banned for eight matches and fined �40,000 after being found guilty of abusing Evra, had attempted to argue that his use of the word "negro" had been inoffensive.
However the FA disciplinary commission said Suarez's evidence had been unreliable in "critically important" areas of the case.
"Mr Evra was a credible witness," the report stated in its summary. "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 between them.
"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 that he pinched Mr Evra's skin in an attempt to defuse the situation. He also said that his use of the word 'negro' to address Mr Evra was conciliatory and friendly. We rejected that evidence.
"To describe his own behaviour in that way was unsustainable and simply incredible given that 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 as to what happened."
Liverpool took the unusual step of rejecting the FA's findings of Suarez in the strongest possible terms earlier this month, with the club denouncing the judgement and insisting Suarez was not a racist.
However the FA panel emphasised it had only been required to make a ruling on the words used by Suarez.
"The charge against Mr Suarez was that he used insulting words which included a reference to Mr Evra's colour," the panel concluded.
"We have found that charge proved on the evidence and arguments put before us. The FA made clear that it did not contend that Mr Suarez acted as he did because he is a racist.
"Mr Evra said in his evidence that he did not think Mr Suarez is a racist. Mr Suarez said in evidence that he will not use the word 'negro' on a football pitch in England in the future, and we believe that is his genuine and firm intention."