Uefa is investigating an alleged case of racist abuse towards Callum Hudson-Odoi during Chelsea’s Europa League win at Dynamo Kiev on 14 March.
Chelsea complained to Uefa after winger Hudson-Odoi, 18, was subjected to monkey chants from some Kiev fans.
Skipper Cesar Azpilicueta told the referee while Blues chairman Bruce Buck also spoke to the Uefa delegate.
If European football’s governing body finds “sufficient evidence” it will “open disciplinary proceedings”.
If Uefa finds a club guilty of racism, it can be punished with “a minimum of a partial stadium closure”.
A second offence is punished with one match played behind closed doors and a fine of 50,000 euros (£42,500).
Subsequent offences are punished with 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.
Hudson-Odoi was also part of the England team, which beat Montenegro 5-1 on Monday night and was subjected to racist abuse from fans.
Uefa has charged Montenegro with racist behaviour, with the case dealt with on 16 May.
Hudson-Odoi, who made his full England debut, said he and team-mate Danny Rose had heard “unacceptable” monkey noises from the home crowd.