Colin Charvis was well marshalled by Leinster

Thomas reduced the arrears after 60 minutes. But the home defence, which had previously been so impressive for Swansea this season, crumbled once more as left-wing John McWeeney dived in unopposed for his side's second try.

There was more to come as Leinster full-back Peter McKenna outstripped the despairing grasp of centre Gavin Henson to feed McWeeney on the inside for another simple score.

Things did not look good for Swansea at 24-12, and matters became worse when they saw international lock Andy Moore shown the yellow card just before the break.

Swansea managed to stem the tide after that. Thomas offered some hope with two more penalties, but Leinster sealed an emphatic triumph with a darting try from lively scrum-half Ben Willis.

Swansea: K Morgan; R Rees, S Payne, G Henson, M Robinson; A Thomas, Robbie Jones; J Marsters, G Jenkins, B Evans, T Maullin, A Moore, C Charvis (capt), D Thomas, H Jenkins.
Replacements: Robert Jones, N Witkowski, G Swales, C Wells, A Le Chevalier, J Griffiths, L Jones.

Leinster: P McKenna; J McWeeney, A Magro, D Quinlan, S Keogh; N Spooner, B Willis; P Coyle, G Hickie, N Treston, B Casey, L Cullen, T Brennan (capt), L Toland, A McCullen.
Replacements: S Barretto, D Blayney, N Breslin, S Jennings, B O'Meara, E Farrell, P Wallace.

Referee: Ian Ramage (Scotland).