Leinster completed an historic Guinness PRO14 and Champions Cup double with a free-flowing 40-32 final victory over Scarlets at the Aviva Stadium.

Leo Cullen’s men ran in five tries and Jonathan Sexton kicked 13 points as they became the first Celtic side to win the domestic and European Cup titles in the same season, a feat their 2011 and 2012 predecessors failed to achieve.

Leigh Halfpenny booted Scarlets into an early 6-3 lead and Johnny McNicholl’s well-taken try cancelled out a Devin Toner effort, but James Lowe’s deftly-finished score on the stroke of half-time had Leinster 21-11 to the good.

Man-of-the-match Sexton stepped up as captain after injury unfortunately ended Isa Nacewa’s 185th and final Leinster appearance in the 18th minute, while Scarlets also lost Aaron Shingler to a knee injury.

The Conference B table toppers put the game beyond Scarlets’ reach with third quarter tries from Sean Cronin and Jordan Larmour, coupled with a further score from Jack Conan.

Time ran out on the defending champions’ late comeback, although the classy McNicholl finished with a hat-trick and replacement prop Werner Kruger also crossed late on.