The English Premier League club have also temporarily excluded five other fans for periods of between one and two years for the use of abusive language and threatening and aggressive behaviour at the fixture on December 8.

Claims City forward Raheem Sterling was racially abused by a member of the crowd during the Blues' 2-0 win were investigated by police but the Crown Prosecution Service ruled there was insufficient evidence to proceed.

Chelsea said they had delayed reaching a decision in the cases in order to ensure they did not prejudice that investigation.

The club concluded, with the use of video evidence, interviews with potential witnesses, and advice from lip-reading experts, that racially abusive words had been used by the fan handed a lifetime ban.

"While the club respects the decision of the CPS (not to charge the individual with a criminal offence), the question that it had to determine was not whether a criminal offence had been committed, but rather whether the individual acted in breach of the ticketing terms and conditions," a club statement read.

"In this regard, the club operates to the civil standard of proof, which is entirely different to the criminal standard.

"In reaching its decision, the club took into account the denial made by the individual as well as a range of other evidence, including video evidence and evidence from two lip-reading experts - both of whom advised that the individual had used words that are racially abusive."

According to the club, all individuals sanctioned as a result of their investigation were offered the right to appeal and, where applicable, those appeals have been heard.

The five fans handed temporary bans from the stadium will be allowed to return subject to "undertakings about their future behaviour".

Anti-discrimination campaigners Kick It Out expressed frustration with the CPS decision but praised Chelsea for sending a "strong message" against racism.

Australian Associated Press