Lyon and former France international Sebastien Chabal could face a year-long ban for punching an Agen player on Saturday.
The back rower landed the punch on Agen's Marc Giraud during Lyon's second division game and will consequently be summoned to appear before the French national league of rugby's disciplinary commission on 3 January.
The maximum ban he could receive for the punch, which left Giraud unconscious, is a year but he could be suspended for as little as two weeks.
The 36-year-old has 62 caps for his country from 2000 – 2011 and is well renowned for his fierce tackling and menacing physique as well as for his long beard and hair which has lead him to be fondly nicknamed 'l'Homme des Cavernes' (the Caveman) by French rugby fans.
Chabal received a yellow card following the incident which he later described as "regrettable but a reflex action" and will await the outcome in the New Year.