Northampton Saints hooker Dylan Hartley has been cited for an alleged headbutt on an opponent.
The 29-year-old has been accused of striking Jamie George during Northampton's defeat to Saracens in the Aviva Premiership semi-finals on Saturday.
If found guilty, the England international could miss the Rugby World Cup.
The maximum length of ban that Hartley can be given is 12 weeks. He is due to face a disciplinary panel on Wednesday.
England start their Rugby World Cup campaign on July 18 when they will take on Fiji at Twickenham Stadium.
