Wasps rugby director Ian McGeechan:
"We were nowhere near the standard we want to be at and our worst two away performances this season have been in the Heineken Cup.
"We are really annoyed with ourselves, but we will be full-on in the next three European games and we intend to hurt a few people if we can.
"The game was nowhere near the pace we would have liked, and we gave all away. You cannot expect to win games if you do that."
Scarlets: Byrne; G Evans, Watkins, D James, M Jones; Bowen, Peel; Williams, Rees, J Davies; Louw, A Jones; Easterby, G Thomas, A Popham.
Replacements: Wyatt for Easterby (65).
Not Used: R Davies, Gravelle, Afeaki, Stuart-Smith, Hercus, B Davies.
Wasps: Lewsey; Sackey, Erinle, Abbott, Voyce; King, M Dawson; Payne, Ibanez, J Dawson; Shaw, R Birkett; Worsley, O'Connor, Dallaglio.
Replacements: Van Gisbergen for Abbott (61), Reddan for M Dawson (80), Barratt for Ibanez (74), Rees for Worsley (63).
Not Used: McKenzie, Skivington, Hoadley.
Att: 7,348
Ref: A Rolland (Ireland).