Incident occurred in defeat to Toulon
Leinster prop Cian Healy could be facing a hefty suspension.
The Irish international has been cited for an act of foul play during Sunday's European Champions Cup defeat to Toulon.
Healy was sin-binned in the first-half for striking Toulon hooker, Guilhem Guirado with his knee on the fringes of a ruck, but the match Citing Commissioner, John Byett has decided that the offence deserves further investigation.
Healy will now have to appear before an independent disciplinary hearing in Paris this Thursday where he could be handed a minimum three-week ban if he is found guilty.