Rhys Priestland will have scans today as Wales and the Scarlets sweat on the fly-half's fitness.
The 25-year-old was stretchered off with an Achilles injury after 47 minutes of the Scarlets' home defeat to Exeter Chiefs.
Priestland slipped while taking the ball into contact and could face an extended period on the sidelines.
"Rhys has got an Achilles injury," said Scarlets head coach Simon Easterby.
"We won't know the extent of that until he has a scan. But it didn't look good."
The Scarlets' woes were compounded by further injuries suffered by Aaron Shingler and Samson Lee.
Shingler, a shining light in Wales' autumn campaign, came off with a groin problem while Lee injured his shoulder.
"Aaron Shingler suffered a groin injury and he's been carrying that for a couple of weeks," added Easterby.
"Hopefully he will come through but that didn't look great either."
The injured trio are just the latest worries for Rob Howley ahead of the 2013 RBS Six Nations.
Adam Jones, Aaron Jarvis, Craig Mitchell, Ian Evans, Alun Wyn Jones and Dan Lydiate all remain on the sidelines, as do George North, Leigh Halfpenny and Jamie Roberts.
But Roberts and Halfpenny are both set to be fit for the Championship with return dates pencilled in for mid-January.
"We've had a few opinions now from the specialists and it seems to be about six weeks will be there time where the nerve will have settled down and it'll be safe to go back to play," added the Cardiff Blues full-back
RGC 1404 have celebrated their crowning as Division One East winners, after just one season of competitive rugby. A big crowd turned out to support the clubs 'Celebration Saturday' when they were presented with the SWALEC trophy following their definitive 45-0 home win against Rhydydfelin on 18 May.
A special video package as Pontypridd claimed the double for the first time in their history by winning the Principality Premiership final, including match build-up, highlights, post match reaction and dressing room celebrations.
Ex-international rugby player Matthew J Watkins has, unfortunately, developed a very rare form of cancer of his right pelvis which requires treatment at Velindre Cancer Centre in Cardiff. He remains well and active and is supported by his friends and family.
We hear from Scarlets and Wales outside half Rhys Priestland on his return from injury in the Principality Welsh Rugby Union Podcast. We also speak to WRU president Dennis Gethin about a new picture of the Queen at the Millennium Stadium, while looking ahead to the Lions with George North, Alun Wyn Jones and Scott Quinnell.
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