Clermont Auvergne flanker Viktor Kolelishvili could face a lengthy ban after being cited for pushing referee Wayne Barnes in his side's European Champions Cup defeat to Ospreys.
In a bizarre incident during the first half of Friday's fixture at the Liberty Stadium, which Ospreys won 21-13, Kolelishvili shoved Barnes - having seemingly felt the official was in his way as Ospreys prepared to play the ball from a ruck.
The Georgian's actions were only punished with a stern talking-to at the time, although Kolelishvili was duly yellow carded following an altercation with Alun Wyn Jones.
On Monday, European Professional Club Rugby (EPCR) announced that Kolelishvili had been cited following a complaint from the match citing commissioner, Mike Rafter.
And the 26-year-old may find himself sidelined for the remainder of the season if he is found guilty at a hearing on Tuesday.
An EPCR statement read: "Under World Rugby's sanctions for foul play, Law 10.4 (m), physical abuse of a match official, carries the following sanction entry points - Low End: 24 weeks; Mid-Range: 48 weeks; Top End: 96+ weeks to life."
While the low-end entry point for the offence stands at 24 weeks, the judicial officer does have the power to reduce any suspension for a variety of mitigating factors. These include the acknowledgment of culpability by the offending player, his conduct at the hearing and previous disciplinary record.
Saracens and England wing Chris Ashton was also cited by EPCR on Monday for "alleged contact with the eye(s) and/or eye area of the Ulster centre Luke Marshall" in Saturday's meeting at Allianz Park.
Glasgow Warriors flanker Ryan Wilson will also be investigated for allegedly grabbing the testicles of Northampton Saints scrum-half Lee Dickson, while Newport Gwent Dragons hooker Rhys Thomas is alleged to have bitten Castres back-row forward Thomas Caballero.
Alexandre Bias of Castres is also facing a disciplinary hearing after he was sent off for a dangerous tackle on Phil Price.