Wales prop Tomas Francis has been cited following an incident during Saturday's RBS 6 Nations defeat against England at Twickenham.
Television footage showed the Exeter forward appearing to make contact with the eye area of England tighthead Dan Cole late in the game, which England won 25-21 to set them up for a Grand Slam tilt in Paris next weekend.
A Six Nations statement on Sunday evening read: "Tomas Francis, the Wales replacement prop forward, has been cited by the independent citing commissioner for allegedly making contact with the eyes or eye area of an opponent [Dan Cole] in the second half of the RBS 6 Nations match between England and Wales at Twickenham on Saturday 12 March 2016. Law 10.4 (m) applies - acts contrary to good sportsmanship."
Match citing commissioner John Cole also issued a formal warning to England back-row forward James Haskell for a dangerous "neck roll" tackle in the 16th minute of the second half of the same match.
If 23-year-old Francis is found guilty at the disciplinary hearing, which is to be held later this week, then he could be looking at a lengthy ban -- possibly 12 weeks or more.
Saracens' England wing Chris Ashton received a 10-week suspension in January for making contact with the eye area of Ulster back Luke Marshall during a European Champions Cup game, although most observers felt it was a harsh punishment.
Speaking immediately after the Twickenham clash, England head coach Eddie Jones said: "I never comment on referees' decisions, especially when we have won a game of rugby. [But] if it was a finger put in the eye, then that should be adjudicated."
Wales head coach Warren Gatland said his initial reaction was he didn't think "it looked great".
Match referee Craig Joubert opted against carding Francis, and the citing commissioner must now decide whether he feels the incident was worthy of a red card or not.
Any lengthy period of suspension for 11-times-capped Francis could see him miss the rest of this season. Exeter are currently strong contenders for a place in the Aviva Premiership play-offs, while they face a Champions Cup quarter-final against Wasps early next month.
Wales, meanwhile, play England again at Twickenham on May 29 before embarking on a June tour of New Zealand that features three Tests against the world champion All Blacks.