Wales boss Wayne Pivac has handed Ospreys flanker Jac Morgan a Test debut in Saturday’s Six Nations clash against Scotland.
Morgan, 22, replaces Ellis Jenkins and lines up at openside flanker in a reshaped back-row that also sees Ross Moriarty start at number eight instead of Aaron Wainwright, with Taine Basham wearing the number six shirt.
Elsewhere, Morgan’s Ospreys colleague – wing Alex Cuthbert – makes a first Six Nations appearance for five years, being preferred to Johnny McNicholl.
But Cuthbert’s fellow wing Josh Adams who started at outside centre in last Saturday’s Six Nations opener against Ireland in Dublin that Wales lost 29-7, is ruled out because of a tight calf muscle, so Owen Watkin fills the number 13 position.
Pivac has resisted any temptation to make further changes, while captain Dan Biggar makes his 100th Test match appearance for Wales and the British and Irish Lions, becoming the ninth Welshman to achieve that feat.
Biggar wins a 97th Wales cap, with Wainwright among the replacements, but McNicholl and Jenkins, who skippered Wales in Autumn Nations Series games against Fiji and Australia this season, drop out completely.
Scotland have not won in Cardiff for 20 years, losing eight Six Nations Tests, a World Cup warm-up game and an autumn international during that time.
But they will arrive at the Principality Stadium following a stirring Calcutta Cup victory over England last weekend that confirmed serious Six Nations title credentials.
Wales, meanwhile, have not started a Six Nations campaign with successive defeats since 2007, and they must beat Scotland to revive any hope of a successful title defence.
15. Liam Williams 14. Alex Cuthbert 13. Owen Watkin 12. Nick Tompkins 11. Louis Rees-Zammit 10. Dan Biggar 9. Tomos Williams 1. Wyn Jones 2. Ryan Elias 3. Tomas Francis 4. Will Rowlands 5. Adam Beard 6. Taine Basham 7. Jac Morgan 8. Ross Moriarty
Replacements: 16. Dewi Lake 17. Gareth Thomas 18. Dillon Lewis 19. Seb Davies 20. Aaron Wainwright 21. Gareth Davies 22. Callum Sheedy 23. Jonathan Davies