The ban rules him out of the Investec last-16 tie at Northampton on Sunday - and a possible quarter-final
John Ryan has been suspended for three matches leaving Munster with just one senior tighthead prop.
Ryan was sinbinned and then cited for a tip tackle on Liam Belcher during the URC win against Cardiff but a disciplinary panel agreed it merited a red.
The ban rules him out of the Investec last-16 tie at Northampton on Sunday - and a possible quarter-final.
If Munster don't progress Ryan will miss the subsequent pair of URC matches in South Africa.

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