Cardiff defender Juan Cala has been charged with improper conduct by the English FA.
The charge relates to an alleged incident in or around the tunnel area after Sunday's Barclays Premier League defeat to Sunderland, the FA said.
Calas was red-carded in the game, after he brought down Conor Wickham. Fabio Borini converted the resulting penalty to help Sunderland on their way to a win that lifted them out of the relegation zone, and compounded Cardiff’s woes.
Cala has until 6pm on Thursday to respond to the charge.
Having already been set to serve a suspension for the Barclays Premier League match at Newcastle, should the charge be proven, then Cala would also miss the final game of the Bluebird's season, at home to Chelsea.
Cardiff are currently bottom of the table and could be relegated if other results go against them this weekend.