Saracens hooker Schalk Brits will have knee ligament surgery and is not expected to be fit until "well into the new year".
Brits, 33, was substituted early in the second half of Sarries' 30-23 victory over Clermont Auvergne in the European Champions Cup on Saturday.
Saracens' head of medicine Joe Collins confirmed the South African would have surgery on Tuesday.
Brits has been with Premiership side Saracens since 2009.
The former Western Province and Golden Lions prop made his international debut in 2008 and has played seven times for his country.