British & Irish Lion Gavin Henson must appear before an independent disciplinary hearing following his clash with Alex Moreno during the Ospreys' 17-15 European Cup defeat by Leicester on Sunday.
Alex Moreno was left with a broken nose after Henson reacted badly to a swinging arm from the Leicester prop and then added to his woes by aiming a kick at the floored Italian which missed.
Henson has been cited by ERC match commissioner Bill Dunlop on two counts - for striking and kicking an opponent.
If found guilty on the kicking charge he faces three months on the sidelines, potentially ruling him out of Wales' entire Six Nations campaign.
However, if the hearing takes account of mitigating circumstances and the centre's previous good record, the length of suspension could be reduced.
A lengthy ban would mark the latest chapter of a miserable six months for Henson, who was forced out of the Lions tour with concussion and then picked up groin and back injuries which excluded him from Wales' November Tests.
The European Cup Pool Three clash with Leicester was his first start of the season after making a substitute appearance against the Tigers the previous weekend.
Ospreys lock Ian Evans has also been called before the disciplinary panel for what appeared to be a kick on Harry Ellis in the same match, leaving the England scrum-half with knee ligament damage.
Leicester are waiting for the swelling to reduce before giving a date for Ellis' return but Tigers head coach Pat Howard described the injury as significant, casting doubt over his involvement in the Six Nations.
Evans has been cited for kicking and could also be facing a three-month ban from the independent disciplinary panel which will hear both cases in Glasgow on Friday.