In a much-changed line-up veteran flanker Justic Tipuric also returns, having missed out in the South of France.
Wales captain Dewi Lake has been ruled out of the fixture with a bicep injury meaning there are wholesale changes to the front-row. Hooker Lake is replaced by Sam Parry, with prop Thomas and Tom Botha also starting.
Will Spencer partners with James Fender at lock. Morgan captains the side and lines up at six, Tipuric takes up the other flank and Morgan Morris starts at eight.
Reuben Morgan-Williams is preferred at scrum-half with his half-back partner Dan Edwards at ten. In midfield, Keiran Williams partners Owen Watkin in the centre.
In the back three, Jack Walsh is at full back, with Keelan Giles on one wing and Dan Kasende on the other.
Scarlets have made two changes with centre Eddie James and full-back Ioan Lloyd starting instead of Joe Roberts and Ioan Nicholas, who both drop to the replacements bench, alongside fit-again Scotland lock Alex Craig.
Wales wing Blair Murray has been ruled out of the clash with a hamstring injury.
Head Coach, Mark Jones, said:
“This is a proud fixture that has been around 20 plus years in the current badges, the history goes back a long way.
“Both teams will be aware of what’s at stake and we’re excited about the opportunity to go up against a very good team.
“Our players and supporters will get themselves ready emotionally right for the occasion.
“Most importantly though, we’ll be looking at our own process and execution. It doesn’t matter who you play in the URC, if you don’t play to your level you’ll get found out.”
Ospreys XV to face Scarlets:
15. Jack Walsh, 14. Dan Kasende, 13. Owen Watkin, 12. Keiran Williams, 11. Keelan Giles,
10. Dan Edwards, 9. Reuben Morgan-Williams
1. Gareth Thomas, 2. Sam Parry, 3. Tom Botha, 4. Will Spencer, 5. James Fender, 6. Jac Morgan (captain), 7. Justin Tipuric, 8. Morgan Morris.
Replacements:
16. Lewis Lloyd, 17. Garyn Phillips, 18. Rhys Henry, 19. Will Griffiths, 20. Morgan Morse, 21. Kieran Hardy, 22. Evardi Boshoff, 23. Iestyn Hopkins.
[Lead image: Ospreys Rugby]
