England internationals Owen Farrell and Joe Marler are among three players cited for foul play in European matches over the weekend.
Saracens fly-half Farrell is alleged to have committed a dangerous tackle on Wasps scrum-half Dan Robson. He could now possible miss the Champions Cup final.
Harlequins prop Marler has been reported for an alleged kick on Grenoble hooker Arnaud Heguy.
If found guilty, Marler could face a suspension of anything between four and 52 weeks depending on how severe the judiciary panel deem the incident.
Meanwhile, Wasps prop Simon McIntyre has also been cited for allegedly kicking Sarries lock Maro Itoje.
Marler was playing for the first time since serving a two-match ban for calling Wales forward Samson Lee “Gypsy boy” during the Six Nations.