Barcelona coach Pep Guardiola is under investigation by the Spanish football federation.
He hit out after the game, accusing the referee Carlos Clos Gomez and his assistants of lying in their explanation of why he had been dismissed and now faces a possible punishment for his post-match comments.
"The competition committee have decided this Tuesday to open extraordinary disciplinary proceedings against Pep Guardiola," read a statement on the Barcelona website.
"The reason is a presumed infraction of articles 66 or 89 of the disciplinary code consisting of 'marked and public acts which threaten sporting dignity and decorum'.
"The competition committee did not pay attention to the declarations presented on Monday by Barcelona.
"The magistrate, Mr Rafael Alonso Martinez, will have a month from today to propose either a stay of proceedings or the list of charges and the punishment to be imposed."