Real Madrid defender Dani Carvajal is being investigated by UEFA after being shown a yellow card in the 6-0 thrashing of APOEL.
The 25-year-old was booked late on by referee Artur Dias Soares at the GSP Stadium on Tuesday night for delaying a throw-in - the only caution of the one-sided match.
There are suggestions that Carvajal deliberately picked up his third caution of the group stage, thus meaning an automatic one-game ban, knowing that next month's meeting with Borussia Dortmund is now a dead rubber.
UEFA's Control, Ethics and Disciplinary Body will further investigate the incident, however, to examine whether the Spain international was guilty of breaching Article 15 of its regulations, which relates to deliberately receiving a yellow card.
UEFA's disciplinary panel will judge Carvajal's case on December 7, with a two-game suspension the worst-case scenario.