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
The SWALEC semi-final draws threw up some mouth-watering clashes in the Cup, Plate and Bowl as the 12 teams aim for the Millennium Stadium Finals Day. All the semi-finals are to be played on the weekend of April 12.
Welsh whistler Rhys Thomas continues to scale the heights of the game as he prepares to be an official in this weekend's Hong Kong Sevens tournament, undoubtedly the showpiece event on the World Series calendar.
Wales International Ian Evans and Wales and Lions legend Scott Quinnell swapped rugby balls for paint pots at Tonna during the RBS 6 Nations. They surprised club players with a special clubhouse makeover to launch NatWest RugbyForce 2014 - a programme developed in partnership with the WRU to make rugby clubs stronger businesses by improving and renovating their facilities with the support of volunteers and the local community.
Fresh from claiming the Bowl honours in Tokyo last Sunday, the Wales Sevens squad have settled into their routine as they prepare for this weekend's Hong Kong tournament where Iolo Evans is aiming high, as WRU TV's Graeme Gillespie discovers.
The Welsh Rugby Union has recently teamed up with Prostate Cymru to help the charity launch its latest campaign to raise awareness of the disease. Members of the Wales squad helped produce a short video and promotional material for the campaign titled 'The Best Defence - is to know the FACTS'.
Defending champions Coleg Sir Gar reached their second consecutive Millennium Stadium final as they defeated Coleg Gwent in the WRU Wednesday Under 18 play-off. Watch highlights of their narrow 10-8 win here.
Wales Sevens head coach Gareth Williams has freshened up his squad for the next two rounds of the World Series in Japan and Hong Kong where Tom Williams, Owen Jenkins and Ross Jones make the trip along with returning Alex Webber and Craig Price.
Judgement Day is coming on the Principality Welsh Rugby Union Podcast. We hear from Millennium Stadium manager Mark Williams, who also reveals details about the Wales Beer Festival. We speak to all four regions about Judgement Day, Dan Baker from the Ospreys, Andrew Coombs from the Dragons, Rob Evans from the Scarlets and Paul John from the Blues. And we have a special look back at the remarkable life of former Wales captain Bert Winfield who fought in the First World War 100 years ago.