Papy Djilobodji, the Chelsea defender on loan at Werder Bremen, is to be investigated by the German Football Association (DFB) for "unsportsmanlike conduct" after making a throat-slitting gesture in a match against Mainz on Saturday.
The 27-year-old made the signal at a grounded Pablo de Blasis after battling for possession with the attacker during the 1-1 draw.
The DFB's monitoring committee have now confirmed they are investigating Djilobodji's actions, which they are able to do after referee Manuel Grafe confirmed he had not seen the incident in his match report.
The DFB have asked Djilobodji for his observations of the incident and would like his response in "a timely fashion" before they decide on the next course of action.
Djilobodji was signed by Chelsea last September in a deal reportedly worth £4million, but he only made one appearance in the League Cup and was promptly loaned to Bremen in January.