Wales suffered a setback shortly before kick-off in their Six Nations finale against Scotland in Llanelli on Saturday when flanker Justin Tipuric was ruled out.
The Welsh Rugby Union said the 77 times-capped Tipuric had been sidelined with tonsillitis.
Scarlets forward James Davies replaced Tipuric in the starting XV and Aaron Wainwright filled the gap left on the bench.
Wales captain Alun Wyn Jones will set a new world record of 149 Test match appearances when he leads the team out at Parc Y Scarlets.
The experienced lock equalled the mark of retired New Zealand World Cup-winning captain Richie McCaw last week.
Wales are seeking to end a run of four successive defeats, They lost38-21 away to France in a warm-up match last week.
Scotland, fresh from a 48-7 thrashing of Georgia, are bidding for their first win on Welsh soil since 2002.