Montpellier's South Africa international back Francois Steyn has lost his appeal against a four-week ban.
Steyn was sent off following a dangerous tackle on Ireland fly-half Johnny Sexton during Montpellier's European Champions Cup defeat against Leinster last month.
Steyn was suspended by an independent disciplinary committee but he lodged an appeal, that was heard by a three-man committee on Wednesday, which was refused, European Professional Club Rugby said.
In a statement, Champions Cup organisers EPCR said: "At last month's disciplinary hearing, the decision to send Steyn off was upheld as it was determined that he had committed a dangerous tackle on the Leinster outside-half, Johnny Sexton, which resulted in reckless contact with the head in contravention of Law 10.4 (e) dangerous tackling.
"To date, Steyn has been suspended for Montpellier's Champions Cup round six match against Northampton Saints, and for the TOP 14 match against Castres Olympique.
"He will remain suspended for the Top 14 matches against Toulouse and Lyon, and will be free to play on Monday, March 6."
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