It is alleged that there was offensive chanting from a section of Chelsea fans during the game in Hungary about Tottenham which referred to the club's Jewish links.
UEFA announced this week that it has opened disciplinary proceedings against Chelsea regarding the matter and a verdict will be reached when the UEFA Control, Ethics and Disciplinary Body next meets on 28th February.
The UEFA Disciplinary Regulations outline if supporters are deemed to have insulted 'the human dignity of a person or group of persons on whatever grounds, including skin colour, race, religion or ethnic origin' the 'club responsible is punished with a minimum of a partial stadium closure'.
It means that if UEFA concludes that Chelsea fans have participated in offensive chanting, sections of Stamford Bridge will be forcibly closed.
But any possible partial closure will not impact the club's upcoming last 32 clash with Malmo as the home leg of the tie is scheduled to take place on 21 February, a week before the UEFA Control, Ethics and Disciplinary Body will discuss the case.
Should they be imposed, sanctions would instead apply to the home leg of the last 16 in March if Chelsea reach that stage of the competition. In the event that they are eliminated by Malmo before then, punishment would transfer to the next European home game, whenever it may be.
UEFA rules dictate that a second offence would be punishable by a €50,000 fine and one match being played behind closed doors. Further offences after that are punishable by 'more than one match behind closed doors, a stadium closure, the forfeiting of a match, the deduction of points and/or disqualification from the competition'.
Source : 90min