Toulouse are facing a deepening crisis after fly-half Lionel Beauxis and flanker Gilian Galan were injured at the weekend.
The pair had just returned to action but had to come off before full-time in Saturday's Top 14 25-5 defeat by Racing Metro.
Toulouse manager Guy Noves said he was unable to say how long either Beauxis (hamstring) or Galan (thigh) would be on the sidelines.
They join an injury list that includes key players who are unlikely to play any further role in Toulouse's season both on a domestic front and their attempt to win a fifth European Cup.
Gregory Lamboley has ruptured right knee ligaments, former All Black fly-half Luke McAlister and France captain Thierry Dusautoir have serious bicep injuries and France centre Florian Fritz has a shoulder problem.
Toulouse travel to Munster in April in the quarter-finals of the Heineken Cup.