Brian O'Driscoll will miss Leinster's Heineken Cup pool match against Castres on Saturday.
The Irish centre is still struggling with a calf injury and will miss his second match in succession with the injury.
He left the pitch injured in the first half against Cardiff Blues on 27 September in the PRO12 and has been struggling for fitness since.
However head coach Matt O'Connor is confident that prop Mike Ross, who left the pitch injured in the first half against Ospreys, will be fit to feature in the clash.
The Leinster team will be named on Friday at noon.