Edinburgh’s losing streak was stretched to six matches as the Scarlets gained revenge for defeat at Murrayfield earlier in the season.
Acting head coach Duncan Hodge must believe his side can show a good deal more than this tame surrender in their European quarter-final next week after they went down by four tries to one.
Phil Burleigh’s lone effort was a fair reflection of a match dominated by the Scarlets, who claimed a bonus point before half-time and then put their feet up.
Hodge will have to hope his players are saving themselves for French club La Rochelle, as they succumbed to their 14th PRO12 defeat in 18 matches.
A pointless second-half from both sides was only a moderate Edinburgh improvement on a first period during which the Scarlets scored with ease.
With nine Scotland players back to reinforce the ranks after Six Nations duty, Edinburgh would have hoped for some early impact. Instead, they conceded the softest of tries in only the third minute.
From the opening scrum, Rhys Patchell worked a straightforward loop around his centres and as the visitors’ defence opened invitingly with the Scarlets outside-half able to stroll all the way to the line from near halfway without a hand laid upon him.
Patchell – playing his first match after three months out with an ankle injury – must have anticipated Edinburgh would at least test his confidence and appetite. But Ross Ford’s men seemed content to afford enough space for the Scarlets’ playmaker to ease himself back into form.
Even though Duncan Weir pulled back three points from a penalty for offside after eight minutes, it proved a rare moment of assertiveness from Edinburgh.
Patchell almost put wing Steff Evans in at the corner with a delicate chip, before constant home pressure was rewarded with a second try midway through the half.
Edinburgh had looked secure enough on their own lineout ball, but when the Scarlets threw in from 25 metres out there was little resistance to a controlled drive that ended with prop Wyn Jones claiming the score.
Patchell’s conversion left Edinburgh trailing 12-3 and already the Scarlets’ slick and powerful back line could sense an early bonus point.
With Edinburgh pinned back deep inside their own half and struggling to make effective first-up tackles, the red tide continued.
Flanker James Davies claimed a third try on 26 minutes when he arrived from deep to finish off a classy backline move that carved Edinburgh open.
It seemed only home errors could hand Edinburgh a way back into the game. The lifeline was given when Ford charged down Aled Davies’s clearing kick and prop Allan Dell fed centre Phil Burleigh, who had a clear run to the posts.
Weir’s conversion made it 19-10, but any thoughts of a comeback before the break were dispelled when Edinburgh conceded a fourth try – and a bonus point – with just more than half an hour gone.
Acting head coach Duncan Hodge must have been dismayed to see the ease with which Jonathan Davies ripped the ball out of Edinburgh hands at a maul. Just as poor was the scrambling defence after the turnover as a long, floated pass by Parkes sent Patchell over.
The same player converted his own try for a 16-point tally as Edinburgh trailed 26-10 at the break.
Hodge’s words must have warmed his players’ ears at the interval and they responded.
Full-back Blair Kinghorn was worked through a gap and it needed a try-saving tackle from Lions hopeful Liam Williams to deny a try.
But aside from a couple of lone charges from Cornell du Preez, Edinburgh were unable to further trouble the solid Scarlets defence.
It might have been worse for Edinburgh had the Scarlets been inclined to try and improve their points difference, but a raft of substitutions by both sides did little to improve the flow of the game in the last quarter.
A disappointed Hodge said: “We were not very good in the first-half – and not much better in the second.
“It was across the board – set piece, defence, it’s just really disappointing.
“To concede the first try in the opening few minutes through a simple defensive error dents the confidence. It rattled us and we lost our composure and thought process – everything we had talked about.
“We stopped conceding in the second-half, but it was still very scrappy. We lost our shape and our decision-making was poor.”
Hodge denied that his players had one eye on next week’s big European clash.
He added: “No, I don’t think next week is an explanation. We were just poor on the night.
“It’s a fresh competition, hopefully that will give us a lift and we are at home. We need to pick ourselves up.
“We are lucky to have a quarter-final next week. It is something to focus on. They are a good side.”
Scarlets: Tries: Patchell (2), Wyn Jones, James Davies. Cons: Patchell (3).
Edinburgh: Try: Burleigh. Con: Weir. Pen: Weir.
Scarlets: J McNicholl; L Williams (DTH van der Merwe 58), J Davies, H Parkes (c), S Evans, R Patchell (D Jones 50), A Davies (G Davies 47); W Jones (R Evans 72), R Elias (E Phillips 58), S Lee (W Kruger 62), T Price, T Beirne, A Shingler, J Davies (L Rawlins 72), W Boyde.
Sub not used: J Barclay.
Edinburgh: B Kinghorn; D Hoyland, C Dean, P Burleigh, T Brown, D Weir, S Hidalgo-Clyne (N Fowles 60); A Dell (M McCallum 55), R Ford (c; S McInally 55), S Berghan (K Bryce 72), A Bresler (G Gilchrist 55), B Toolis, V Mata, J Ritchie (V Fihaki 39), C Du Preez.
Subs not used: J Tovey, G Bryce.