Chelsea has issued a lifetime ban to a fan for using "racially abusive language" following an investigation into an incident involving Manchester City winger Raheem Sterling.
England international Sterling was allegedly subjected to racial abuse as he retrieved a ball during the Premier League encounter between City and Chelsea at Stamford Bridge in December.
Blues supporter Craig Wing admitted to shouting an obscenity at the 24-year-old but denied his comments were "racial in nature" and the Crown Prosecution Service subsequently announced it would not initiate any criminal prosecutions.
Chelsea reviewed evidence and sought expert opinions from two lip reading professionals before announcing the outcome of its own investigation on Tuesday.
One individual has been issued with a permanent ban from the club's home venue and five others have been barred from attending for periods ranging from one to two years.
"We understand that this incident has been the subject of discussion amongst supporters, and the club appreciates that emotions can run high during matches," read a statement from the Premier League side.
"However, in this case the behaviour of all six individuals crossed the line of what is acceptable.
"Furthermore, in the case of the supporter who was found by the club to have used racially abusive language, there is no place for this behaviour at Stamford Bridge and a permanent exclusion was the appropriate sanction.
"Given the particular circumstances of this case, the club did not consider that attendance at an education course in return for a reduced sanction would have been appropriate."
The sanctions come in the wake of manager Frank Lampard's appeal for fans to cease using an offensive chant aimed at rivals West Ham that was heard during Sunday's friendly against Reading.
Chelsea added: "We are clear and consistent in our condemnation of discriminatory behaviour and language and all fans should remember that their words and actions can cause offence to those around them and to the wider community.
"We will continue to work with our supporters to rid the game of all forms of discrimination."