The fly half injured his neck during the 32-26 EDF Energy Cup defeat to Saracens last week and despite management hopes of his return this weekend, he will be replaced by Rhys Priestland.
Scarlets Director of Rugby Phil Davies says his side need a 100% record in the rest of the Heineken Cup to have a chance of the quarter-finals.
“That’s the long and short of it, we have to win them all starting with Munster,” said Davies, whose side have fallen to Clermont Auvergne and Wasps.
“Each of the remaining pool games are like cup finals to us. We cross paths regularly with Munster and we have huge respect, they stand for everything that is good in rugby.”
Hookers Matthew Rees (hand) and Ken Owens (knee) plus three-quarter Dafydd James (groin) remain on the casualty list. Jonathan Edwards, Lee Williams and Rob McCusker are on Wales Sevens duty.
Scarlets: M Stoddart; M Jones, R King, Gavin Evans, N Brew; R Priestland, D Peel; I Thomas, J Hayter, D Manu, A Eustace, S MacLeod, S Easterby (Capt), G Thomas, D Jones
Replacements: D George, B Douglas, V Cooper, A Popham, G Cattle, C Thomas, J Davies
Munster: S Payne; B Carney, R Tipoki, L Mafi, I Dowling; R O’Gara (capt), P Stringer; M Horan, J Flannery, J Hayes, D O’Callaghan, M O’Driscoll, D Leamy, D Wallace, A Foley
Replacements: F Sheahan, T Buckley, D Ryan, J Coughlan, G Hurley, P Warwick, K Lewis
Referee: Wayne Barnes (England)
