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
Wales Under 18 captain Calum Haggett has received a conditional offer to read Biomedical Science at St Anne's College, Oxford. WRU chairman Gareth Davies went to meet Calum and Coleg y Cymoedd Principal Judith Evans to wish him luck in his exams and pass on some of his personal experience.
Gemma Rowland has had a 'whirlwind' start to her international career with Wales. Despite losing to France, she is confident Wales Women can bounce back and claim a rare Triple Crown against Ireland on Sunday, as WRU TV's Graeme Gillespie discovers.
The Wales teams return home for the Irish leg of their Six Nations campaigns in this week's Principality Welsh Rugby Union Podcast. We speak to Wales attack coach Rob Howley and defence coach Shaun Edwards, as well as flanker Dan Lydiate and full back Leigh Halfpenny. We hear from Wales Women's back rower Sian Williams and Wales U20 forwards coach Chris Horsman and flanker Ollie Griffiths.
Wales look to build on victory in Paris in this week's Principality Welsh Rugby Union Podcast. We hear from coach Warren Gatland and captain Sam Warburton, as well as Wales Women's coach Rhys Edwards. We also hear from Wales U20 duo Dan Jones and Joe Davies, along with Wales U18s.
We look ahead to the French tests in this week's Principality Welsh Rugby Union Podcast. We look ahead to Wales France with Warren Gatland, Sam Warburton, Scott Baldwin, Rhys Webb and Jonathan Davies. Wales Women are the only team in red still unbeaten in this Six Nations, we speak to captain Rachel Taylor. Wales U20 are looking bounce back from defeat in Scotland, we hear from coach Jason Strange, captain Rory Thornton and front rower Dillon Lewis.
Warren Gatland and Sam Warburton look ahead to this week's crunch RBS 6 Nations tie against France, where the Wales skipper in particular is keen to make his mark, as Paris has proved a bleak place for him in the past.
The Principality Premiership awards and the Wales U20s get ready for the world cup in this week's Principality Welsh Rugby Union Podcast. We hear from coach of the year, Ebbw Vale's Jason Strange and Wales scrum half Rhys Webb. We also speak to Wales U20s Rory Thornton, Harrison Keddie, Tom Phillips and Geraint Lewis.
The Guinness PRO12 play-off away team hoodoo continues after the Ospreys were robbed of victory at Thomond Park despite crossing the Munster line for what seemed to be a match winning try with the last move of the match.
Pontypridd claim the Principality Premiership title - we speak to captain Dafydd Lockyer and coach Gareth Wyatt on the Principality Welsh Rugby Union Podcast. We also hear from losing finalists Ebbw Vale and their coach Jason Strange, while Steve Tandy and Dan Baker look ahead to the Ospreys Guinness Pro12 semi-final in Munster and Wales U20 defence coach Richard Hodges talks about the Junior World Championships.
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