John Terry has been given until 18 October to appeal his ban after the FA published written reasons for the Anton Ferdinand verdict.
A Regulatory Commission dismissed as "implausible" Terry's defence that he was repeating a racial slur he thought Ferdinand had accused him of using during Chelsea's game at QPR in October 2011.
Instead it found that in all likelihood Terry lost his cool after a heated exchange with Ferdinand and used the phrase as a straightforward insult.
And, although Terry was cleared in a criminal court in July, the FA was able to judge the case according to "the flexible civil standard of the balance of probability" and hand down a four-match suspension.
The Commission found aspects of Terry's defence to be "improbable, implausible and contrived" and was "quite satisfied, on the balance of probabilities, that there is no credible basis for the defence that...the words were directed at Ferdinand by way of forceful rejection and/or inquiry."
Terry's ban is half the length of the eight-match suspension Liverpool's Luis Suarez was given for racially abusing Manchester United defender Patrice Evra last season.
The difference between the cases, according to the report, is that "Mr Terry's racist insult was issued only once" whereas Suarez was found guilty of repeating his.
And the Commission's findings made it clear "it is accepted by everyone involved in the criminal and disciplinary proceedings that Mr Terry is not a racist."
Team-mate Ashley Cole's evidence was also scrutinised after amendments were made to his initial witness statement - according to the FA, "with a view to bolstering Mr Terry's" defence.
The Commission questioned whether Cole had changed his account after discussions with David Barnard, the Chelsea club secretary whose own evidence caused "very real concerns" and was not addressed by the Chief Magistrate in his judgment of Terry's criminal case.
The commission found that there were discrepancies in Cole's initial statement to FA interviewers of what he heard Ferdinand say to Terry compared to later statements.
Cole did not mention the word 'black' in the initial interview with the FA on October 28. On November 3, Barnard asked the FA for the specific word 'black' to be inserted into Cole's witness statement, suggesting that Cole may have heard Ferdinand use the term.
The commission saw an email exchange between the FA and Barnard and said that should be regarded as "cogent new evidence".
The commission said: "These highly material issues relating to Mr Cole's evidence were not addressed by the Chief Magistrate - he clearly did not have the interview notes of the FA's interviewers, or Mr Barnard's statement before him - and they do not appear in his judgment.
"Accordingly, that material can and should properly be regarded as cogent new evidence.
"Had it been before him, the commission has no doubt that the Chief Magistrate would have examined Mr Cole's evidence as to what he claims he heard Mr Ferdinand say to Mr Terry on the pitch very carefully indeed, or scrutinised it even more closely than he may have done."
It adds: "All of this causes the commission to have very real concerns about the accuracy of Mr Barnard's recollections, and the motivation for the assertions that he makes in his witness statement about what Mr Cole said during the FA interview of him, particularly his alleged use of the word 'black'."
Ferdinand had suffered "hateful abuse" as a result of the case but had acted with dignity, said the report.
The commission stated: "The victim impact statement of Mr Ferdinand makes it plain that he has been badly affected by the incident. He has been the subject of hateful abuse and adverse comments, but has acted with restraint and dignity."