King missed the final two Heineken Cup matches against Clermont Auvergne and London Wasps with a rib injury. But King, who figured in every minute of the Scarlets campaign last season, is back to boost their title challenge.
Scarlets Director of Rugby Phil Davies said: “This weekend is key for us. We’ve got eight games left, five at home, three away and we have a great run-in.
“There’s a real opportunity for us to come up on the rails and provide a satisfying finish to the season. We’ve had a pretty dire period when a lot of things haven’t gone as well as we would have liked but hopefully it’s a fresh start for us this weekend.”
Wales No.8 Alix Popham has been released by national boss Warren Gatland but has not been named in the 22 while skipper Simon Easterby returns from RBS Six Nations duty for Ireland to start on the bench.
James Bater takes over the captain’s armband while Samoan World Cup hooker Mahonri Schwalger makes his full debut at Stradey Park.
Scarlets: M Stoddart; D James, R King, G Evans, M Watkins, R Priestland, G Cattle; I Thomas, M Schwalger, D Manu, V Cooper, L Reed, D Jones, N Thomas, J Bater (Capt)
Replacements: P John, D George, D Day, S Easterby, L Davies, C Thomas, D Daniel