The 33-year-old Jones injured his knee in last weekend's Heineken Cup victory over Benetton Treviso and has been told he can expect to be out of action for the next month.
The Scarlets medical team re-assessed the injury today and confirmed that early signs indicate that he has a minor knee ligament strain. If he is ruled out for a month, then he will miss the Scarlets' games against the Ospreys (26 December), the Dragons (1 January) and Edinburgh (7 January).
On the broader front, he will definitely sit out his side's weekend trip to fellow Magners League outfit Benetton Treviso in Europe this weekend, but should come back into the reckoning for Rounds 5 and 6 of the Heineken Cup in the New Year.
The Scarlets are also facing injury worries over Wales skipper Matthew Rees, who will have a late fitness test this week to see if he is available for the trip to Treviso this weekend. Rees is carrying a minor adductor strain in his groin.
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