Rob Higgitt comes in at outside centre and new skipper Mark Jones makes his first start of the season, teaming up for the first time with Scotland cap Sean Lamont on the opposite wing.
Scarlets team manager Garan Evans said: "Last weekend's game against Bath at Parc y Scarlets was a useful exercise and we expect to step up a gear this weekend.
"We hope to raise the intensity and look forward to trying out a few more new combinations. Bath will provide another strong test as we look forward to our first Magners League game the following weekend.
"There's a great tradition of rivalry between the Scarlets and Bath - and we're looking forward to renewing those acquaintances at the Rec."
Scarlets (v Bath, away)
1. Iestyn Thomas
2. Ken Owens
3. Rhys Thomas
4. Lou Reed
5. Dominic Day
6. Dafydd Jones
7. Johnathan Edwards
8. David Lyons
9. Martin Roberts
10.Daniel Newton
11.Sean Lamont
12.Jon Davies
13.Rob Higgitt
14.Mark Jones (c)
15.Daniel Evans
16.Phil John
17.Deacon Manu
18.Emyr Phillips
19.Damien Welch
20.Simon Easterby
21.Richie Pugh
22.Lee Williams
23.Andy Fenby
24.Gareth Maule
Photo Scarlets prop Iestyn Thomas
