Dean Mumm will face no further sanction for his dangerous tackle on Ireland's Tadhg Furlong, leaving him free to face England at Twickenham on Saturday.
The Australia flanker was sin-binned for picking up Furlong and dropping him on his head at a ruck during Ireland's 27-24 victory at the weekend.
Mumm was called in front of a disciplinary panel in London on Tuesday, where it was found that his yellow card was sufficient punishment.
"The Disciplinary Committee concluded that, although Mr Mumm had committed an act of foul play (as he had accepted), the particular circumstances of the incident meant that Mr Mumm's actions would not have warranted a red card," a statement read.
"Accordingly, no sanction was imposed and Mr Mumm is therefore free to resume playing immediately."
Mumm and Australia are hoping to bring an end to England's otherwise perfect year, with Eddie Jones' side having won all 12 Tests in 2016 - including a 3-0 series whitewash of the Wallabies down under in June.