Captain Aurelien Rougerie is a doubt for Clermont's bid for Heineken Cup glory against Toulon in Dublin on Saturday.
France international Rougerie missed training on Monday after suffering a thigh strain against Toulouse on April 20.
Rougerie was forced to sit out the semi-final victory over Munster and although he has yet to return to full training he has now started light running.
Rougerie will undergo a fitness test on Thursday, with Gerhard Vosloo and Daniel Kotze also struggling to take their place in the side.
Flanker Vosloo has a thigh issue, while tighthead prop Kotze has a back problem.