A foot injury will put Gethin Jenkins out of service when the Cardiff Blues' take on Newport Gwent Dragons on Friday in the Magners League
The British and Irish Lions prop is a confirmed absentee but there are also doubts over Wales flanker Martyn Williams (ribs), hooker Gareth Williams (shoulder) and former New Zealand centre Casey Laulala (knee) are also doubts for the Blues.
Dragons wing Aled Brew is a doubt as he bids to recover from an ankle injury.
While lock Adam Jones and flanker Dan Lydiate are out for the season but centre Ashley Smith could return.
Dai Young's men will also be without Wales duo scrum-half Gareth Cooper and centre Tom Shanklin due to injury.
And Wales wing Tom James is definitely out injured for the Blues while number eight Andy Powell has recovered from a calf injury.
While Blues lock Deiniol Jones is set to break the Magners League appearance record as his 118th league game would eclipse Dragons prop Adam Black's record.
The Blues hope to extend their winning run over the Dragons to seven games although the Rodney Parade region have only lost once at home this season - to another Welsh region Llanelli Scarlets.
The Cardiff side are bidding for their fifth successive victory and hoping to extend their impressive form of six successive wins in all competitions.
The Dragons and Blues have already qualified for the Heineken Cup next season but both are chasing an outside spot for the top-four end-of-season play-off.
As the countdown continues for RWC2015, Tournament Chief Executive Debbie Jevans visited the Millennium Stadium to discuss preparations for the eight matches and reveal the positive news that 100,000 tickets for games at the home of Welsh rugby have sold in the last seven days.
Jason Harries is targeting a first win on the World Series circuit this season with Wales. The series returns to action this weekend in Dubai where Harries is part of a team hoping to build from its efforts in round one in October.
Wales skipper Jevon Groves says his side have addressed a few points from Gold Coast and aim to 'hit the ground running' in the next two rounds of the World Series, kicking off with this weekend in Dubai before heading off to South Africa next week.
Wales Sevens manager Steff Thomas is hopeful his side can build from a quarter-final spot in the opening round of the World Series in Australia when his side take part in the forthcoming double header in Dubai and South Africa.