The 23-year-old Wales A forward, who joined the Stradey Park club in the summer, suffered a freak accident on the training ground.
The Scarlets’ 21-29 home defeat to Connacht was their fourth loss of the season and they next face the Heineken Cup visit of mighty Toulouse on the 22nd October.
‘Facing Toulouse after the loss is more daunting,’ said coach Nigel Davies.
‘It would be a tough Heineken Cup pool if we were top of the Celtic League, but it’s that much more difficult now.’