Manchester United defender Jonny Evans's actions in spitting at Papiss Cisse were "simply disgusting", said the FA panel which found him guilty.
"The ordinary man in the street will find his action to be simply disgusting," said the three-man panel.
"It should not be allowed in any walk of life, let alone any football field."
The written reasons for the punishment given to Evans and Cisse, 29, were released by the FA on Thursday.
Manchester United argued that a six-match ban against Evans was excessive, the report also revealed.
Cisse, who accepted the original charge, will miss seven games through suspension for his part in the incident.
The Senegal international misses an extra match because he was banned in December for elbowing Everton's Seamus Coleman.
|Games that Evans and Cisse will miss|
|Jonny Evans: Arsenal (H - lost 2-1), Tottenham (H), Liverpool (A), Aston Villa (H), Manchester City (H), Chelsea (A)|
|Papiss Cisse: Everton (A), Arsenal (H), Sunderland (A), Liverpool (A), Tottenham (H), Swansea (H), Leicester (A)|
"It is clear that Mr Evans is looking directly and indeed aggressively at Mr Cisse. His lips are 'pursed' and he is close to Mr Cisse," added the report by an independent regulatory commission.
"If he was, as alleged to be the case, a person who 'habitually spits', then the commission were concerned as to why he did not turn his head away from Mr Cisse when so spitting.
"If that had been a family member or indeed another team member or his manager in front and below him would he still have carried out the same manoeuvre?
"Mr Evans had (and has) a duty of care, if spitting for whatever reason, not to direct the same in the general direction of an opponent, or indeed anyone else. The video clips clearly show that he failed in his duty of care."
Manchester United and Evans accepted that spitting has "no place in football", but hoped that the Northern Ireland international would receive less than a six-match ban.
But the panel, which admitted Evans had a "good and maybe commendable" previous disciplinary record, did not believe there were any exceptional circumstances to warrant a lesser punishment.