Wales will be without Alun Wyn-Jones for the visit of Scotland on Saturday after the Ospreys lock suffered damaged ankle ligaments.
Wyn-Jones picked up the injury in the surprise 26-19 victory over England at Twickenham on Saturday - however he should be cleared to return to face Italy on February 23.
In his absence, Warren Gatland has called up 30-year-old Cardiff Blues lock Deiniol Jones to the squad - although Ian Evans is likely to start.
Jonathan Thomas is also a doubt for the clash - with the flanker undergoing tests after lasting barely 15 minutes at Twickenham.
Thomas was caught around the head by Jonny Wilkinson - although Wales have not complained about the tackle.