Sebastien Vahaamahina has been handed a six-week ban following his red card in the Rugby World Cup quarter-final between France and Wales.
The France second row was dismissed for inexplicably elbowing Aaron Wainwright in the head in the 49th minute of Les Bleus' 20-19 defeat last Sunday.
His indiscipline proved costly as Wales overturned a 19-10 deficit to prevail and set up a semi-final with South Africa.
Vahaamahina announced his retirement from international rugby a day later, but he will now not be able to play for Clermont Auvergne until December 16 after a decision made by an independent judicial committee following a disciplinary hearing he attended via videoconference on Thursday.
A World Rugby statement read: "Vahaamahina admitted the act of foul play, that he had contacted his opponent's head intentionally and accepted that it warranted a red card.
"The committee considered that the terms of High Tackle Sanction Framework were relevant and accepted the player's admission that: There was a strike, there was direct contact between the player's elbow and Aaron Wainwright's jaw, there are no mitigating factors.
"The committee upheld the red card and considered this to be top-end offending. This resulted in a starting point of a 10-week suspension.
"Taking into account the mitigating factors that are considered in relation to sanction, including the player's early and full acknowledgment of his conduct and prompt apology to his opponent, the committee reduced the 10-week entry point by four weeks, resulting in a sanction of six weeks."
Vahaamahina's first opportunity to make his return will be in the Top 14 clash with Toulon on December 21. He will miss Clermont's first four Champions Cup matches as a result of his suspension.