Scarlets' Samoan lock Maselino Paulino has been cited for allegedly striking Northampton's England lock Courtney Lawes in their European Champions Cup defeat on 23 January.
Paulino was sin-binned at the time, but faces a hearing in London on Wednesday.
If suspended, Paulino will, at least, miss Scarlets' Pro12 clash at Connacht on Saturday.
Scarlets boss Wayne Pivac has revealed Paulino will leave for France at the end this season.
He has been linked with French club Lyon.