Racing 92 hooker Dimitri Szarzewski has been ruled out for the rest of the season due to a hernia operation.
The former France international will miss Racing's bid to make the Top 14 play-offs with the final few weeks of the campaign remaining.
Szarzewski's injury comes as a major blow for Racing, with promising young France hooker Camille Chat still on the road to recovery after suffering a biceps tear.
Szarzewski is also Racing's captain and his presence will be missed with the defending champions right in the middle of a tight chase to make the knockout stages.
Racing travel to Toulouse on Sunday, with Virgile Lacombe in line to start with Szarzewski and Chat ruled out.