CSKA Moscow could be thrown out of the Champions League and banned from future competitions because of positive drugs tests for two of their players following a match against Manchester United.
Russian defenders Alexei Berezutsky and Sergei Ignashevich have been provisionally suspended from all games after positive doping tests for a banned stimulant.
The random tests were carried out following the Champions League clash with Manchester United on November 3 which ended in a 3-3 draw.
UEFA's disciplinary committee will hear the case on December 17 but under the European body's regulations, if more than one player tests positive for banned drugs action can be taken against the team.
Part of Article 12 of UEFA's disciplinary regulations states: "If more than one player from the same team is charged with a doping offence in relation to a prohibited substance or methods the team in question may be disqualified from the competition in progress and/or future competitions.''
The Russian club have defended the players and claim it was down to a "clerical error''.
CSKA claimed that both players had been given Sudafed while battling colds on international duty, but CSKA's medical staff had failed to include the medication on a list handed to UEFA following the clash with United.
"The problem is that during the doping control procedures a clerical error was made by employees within our medical staff,'' said the statement on www.pfc-cska.com.
"For the players and for the club this news was truly shocking.
"Unfortunately, we do not yet fully understand all the circumstances of the case, but we have nothing to hide, and we believe our fans should be made aware of that.
"This situation has arisen in connection with the treatment of our players from a severe cold during their time with the national team, and not in any way with doping, which is also known by the relevant bodies within UEFA.''