Fifa have given Wayne Rooney until Thursday to file a statement over his red card in England's World Cup quarter-final defeat by Portugal.
Cristiano Ronaldo will not be investigated over his involvement in the sending-off.
Rooney was dismissed just an hour into the match after appearing to stamp on Chelsea and Portugal defender Ricardo Carvalho.
Ronaldo was immediately in the referee's eyeline demanding a card for Rooney, prompting his Man United teammate to push him away in frustration.
Ronaldo's actions incensed Rooney and his fellow England players, especially as they were instructed throughout the tournament that such behaviour would warrant a card.
Rooney was not spared the red however, and left the field to watch his side struggle and ultimately fail again at the penalty shoot-out stage.