The Scarlets had their pride dented as Leinster, rival candidates for the PRO12 play-off spots, grabbed a bonus point in a 32-5 victory in Dublin.
The hosts scored tries through Andrew Goodman, Aaron Dundon, Jordi Murphy and John Cooney.
Andy Fenby touched down for the Llanelli side's only try, as Leinster added 21 unanswered points after the break.
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A dry start with long sunny spells. Cloud will thicken during the afternoon.
Sunshine in the north this evening, but cloudy in the south.
Hundreds of people gathered in Cardiff for International Yoga Day. Young and old came together to learn about the ancient Indian discipline