Wales wing Shane Williams is battling to be fit for the RBS 6 Nations Championship clash against Ireland in Dublin.
The Ospreys speedster is suffering from a dead leg and has yet to resume full training, while captain Gareth Thomas is recovering at home after going to hospital in Bridgend on Sunday night suffering from a severe migraine.
Newport Gwent Dragons back Ceri Sweeney is a confirmed non-starter on Sunday because of a groin injury, but his fellow centre Matthew Watkins has recovered from a leg injury sustained during the 28-18 victory over Scotland eight days ago.
"Matthew is taking a full part in training, but Shane will not get fully involved for a further couple of days," said Wales team physio Mark Davies.
"Ceri (Sweeney) is almost three weeks down the road to recovery from his groin injury but is also unable to participate in full team training at the moment and he has been ruled out for the weekend's match."