Australia flanker Michael Hooper has been cited for alleged foul play during the Wallabies' 33-13 victory over England at Twickenham on Saturday.
World Rugby announced that Hooper has been reported by independent citing commissioner Steve Hinds for allegedly "charging into a ruck or maul without use of the arms or grasping the player".
Hooper will now face a disciplinary hearing in London on Tuesday.
The incident happened just before half-time when Hooper challenged England full-back Mike Brown.
Australia's win dumped England out of the World Cup, and Hooper played a pivotal role in setting up a Pool A decider against Wales at Twickenham next Saturday.
Alongside David Pocock and Scott Fardy, Hooper is part of arguably the tournament's most effective back row, but his participation against Wales - and possibly beyond that - could now be in doubt.
Sanctions for charging range from a two-week ban at the lower end of the scale, through to five weeks if it is classed as mid-range, or 10 weeks and above if viewed as a top-end offence.
In a statement, World Rugby said: "Michael Hooper has been cited by independent citing commissioner Steve Hinds (New Zealand) for an alleged act of foul play contrary to law 10.4 (h) (charging into a ruck or maul without use of the arms or grasping the player) during the 39th minute of the Rugby World Cup 2015 Pool A match between England and Australia on Saturday, October 3.
"The hearing will take place at 1000 on Tuesday, October 6 at the offices of RWC official law firm Clifford Chance in London. The case will be heard by independent judicial officer Alan Hudson (Canada)."