Wales captain Scott Quinnell will face the Welsh All Blacks and then miss the next two Celtic League matches, at home to Ebbw Vale and away in Edinburgh, after opting for surgery on his troublesome nose.
The big No 8 has suffered from regular nose-bleeds since he took a knock on his hooter during the British Lions tour of Australia.
He will be out for two weeks, but the Scarlets have Dave Hodges back after his duties for the United States team.
Coach Gareth Jenkins said: "It is a great blow to the side to lose someone of the calibre of Scott, but we have a strong squad to choose from and it is best to get the problem sorted sooner rather than later."
Wales U20 captain Tom Phillips and performance psychologist Dr Rich Neil explain why spending three days at Monmouth RFC has further strengthened the togetherness of the squad ahead of the #WorldRugbyU20s
Alongside Scarlets flanker James Davies and Cardiff Blues centre Cory Allen, three Wales Sevens core players have made the extended training squad for GB Sevens. Wales Head coach Gareth Williams tells WRU TV's Graeme Gillespie why Luke Treharne, Sam Cross and Luke Morgan earned selection in the initial training squad for Rio.
Wales Sevens head coach Gareth Williams tells WRU TV's Graeme Gillespie he has had to overcome a number of injuries before naming a competitive squad for this weekend's penultimate round of the World Series in Paris.
Merthyr were officially crowned champions of the SSE SWALEC Championship at Dowlais on Saturday where captain Andy Powell paid tribute to his side who have earned promotion to the Principality Premiership
Coleg y Cymoedd's season has had a spectacular ending with victory in two cup finals and a massive victory over one of the best rugby playing schools in the world - Welsh coach Warren Gatland's old alma mater, Hamilton Boys' High School.
WRU chief executive Martyn Phillips hosted the second meeting of the WRU Youth Board last weekend ahead of the Judgement Day IV regional double-header. Tthe board, made up of 15 under-21-year-olds from around Wales, heard presentations from head of participation Ryan Jones, policy and integrity manager Jeremy Rogers and national women's rugby manager Caroline Spanton, with Pro Rugby Wales CEO Mark Davies also on hand to hear the range of views aired.
Wales duo Rhun Williams and Liam Belcher, who makes a welcome return after five months of injury woe, look ahead to next month's World Rugby U20 Championship in Manchester where they will face Ireland, Georgia and New Zealand.