Ireland's Sean O'Brien has been cited for foul play following his team's victory over France in the World Cup on Sunday.
The flanker appeared to punch France lock Pascal Pape in the stomach in the early stages of the Pool D match at the Millennium Stadium in Cardiff and will have his case heard on Tuesday.
Independent judicial officer Terry Willis will hear O'Brien's case in London and the Leinster forward could face a ban which would rule him out of this Sunday's quarter-final against Argentina back in Cardiff.
Neither referee Nigel Owens, nor television match official (TMO) Graham Hughes, picked up the incident between O'Brien and Pape although footage of the tangle quickly spread around the internet.
France coach Philippe Saint-Andre was unhappy with the incident and that O'Brien went unpunished during the game.
He said: "It was an assault after just 23 seconds of the game. I hope the next time the TMO will really do his job.
"Since the beginning of the competition on whatever matter is concerned, try or injury, we return to a review of the images. In this case they do no such thing."
Ireland coach Joe Schmidt had been hoping that O'Brien would avoid a citing.
Schmidt said after the game: "He was being held at the time, he swung but I don't think he was looking directly at the player but it's not for me to determine. It's not a closed fist. I'd be hopeful but it's not a decision for me. Hopefully it's not something that impacts on us.
"Considering the dressing room at the moment, we can ill-afford to lose another player, particularly a player of Sean's experience and standing in the group."
The potential loss of O'Brien is a serious problem for the Irish with flanker Peter O'Mahony ruled out of the remainder of the tournament after picking up a knee injury against Ireland and skipper Paul O'Connell facing a similar fate due to his serious hamstring injury.
Argentina could also lose a player for the last-eight clash after centre Marcelo Bosch was cited for a dangerous tackle during the Pumas' Pool C match against Namibia.
Meanwhile, Tonga hooker Paula Ngauamo has been banned for three weeks for a dangerous tip tackle on Daniel Carter in the 47-9 defeat to New Zealand.
Ngauamo was yellow-carded for the tackle on Friday and admitted the charge after being cited, with Willis imposing the suspension.
Willis deemed the tackle at the low end of the scale for the charge and Ngauamo will serve the ban at his French club Mont-de-Marsan, where he can resume playing on October 31.