Cardiff Blues are sweating on star Wales centre Jamie Roberts being fit for the final two Pool 6 matches in the New Year - away to Toulon and home to Sale Sharks.
The Blues have only banked one losing bonus point so far and have now been told that Roberts could be sidelined for up to six weeks.
The British & Irish Lions star, who suffered a hyperextension of his elbow in last weekend's agonising 14-12 defeat to Australia, saw a specialist yesterday and was informed of the lengthy time on the sidelines.
The powerful centre heads an alarming injury list for the Blues, who are also without Leigh Halfpenny and Bradley Davies.
Halfpenny is recovering from a severe stinger and continues to be assessed and Davies is expected to return to training next week following severe concussion.
Blues director of rugby Phil Davies said: "Only a fortnight ago things were looking very positive for us, when we were welcoming back some key players.
'However, we have been extremely unfortunate to pick up a raft of injuries in the last few weeks.
"It is frustrating that we cannot select from a full strength squad for these crucial matches, but on a positive note, it gives a chance for some of our other players to step up and show what they can do."