Leinster will be without Hayden Triggs for their final Champions Cup pool game with Castres after the lock received a three-week ban.
The suspension is for making contact with the eye area of Montpellier's Nick White during last Friday's win at the RDS.
It had been feared a longer ban might rule him out of Leinster's quarter final.
Meanwhile, Montpellier's Francois Steyn has been handed a four-week ban for his late challenge on Jonathan Sexton.
"It's going to have to be red." Montpellier's Frans Steyn is sent off by ref JP Doyle for a dangerous high tackle... https://t.co/iUa9bcZiXH
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