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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Any lingering showers will ease this evening, to leave a dry night with plenty of clear spells. Minimum temperature 11 deg C (52 deg F).
Blackwood mother Trudy Jones was on holiday when she was gunned down in the Tunisian beach massacre that claimed the lives of 30 Britons.
The pair, including a man in his 50s, were struck around midday on the Pen y Fan mountain range in Powys, mid-Wales.