Despite a red card for Steff Evans the Scarlets pulled off a major shock in Dublin
They became the first side in history to win a PRO12 semi-final away from home
Ospreys were the last Welsh club to win the competition in 2012
Scarlets produced a historic performance to beat Leinster in the Pro12 semi-final despite having winger Steffan Evans sent off before half-time.
The winger was red-carded for a tip tackle on centre Garry Ringrose in the 38th minute when Scarlets were leading 21-10.
Evans, back-row Aaron Shingler and scrum-half Gareth Davies scored fine tries for the visitors.
Centre Ringrose and number eight Jack Conan touched down for the home side but it wasn't enough, meaning they miss out on the 27 May final in Dublin.
The victory will without a doubt go down on the honours board at Parc y Scarlets alongside even the legendary victories against New Zealand and Australia.
Following the win, Scarlets coach Wayne Pivac has taken a veiled swipe at the Wales management for continually ignoring flanker James Davies, who starred in what was probably his best performance to date.
"I have said from day one he is a fantastic player. I rate him very highly," said the New Zealander.
"His performances over three seasons now, not one or two weeks like some of the other players, have been top drawer.
"As a group we support James. If we had a choice between him and other top opensides in the country we would take James every day.
"I think you saw his worth out there. Put him on the wing and he doesn't flinch, he just goes out there and does a job.
"His positioning and reading of the play is fantastic. He has a great skillset and a very, very big heart.
"Our boys had to dig deep and he was one who did that."
The scorers:
For Leinster:
Tries: Ringrose, Conan
Con: Nacewa
Pen: Nacewa
For Scarlets:
Tries: S Evans, A Shingler, G Davies
Cons: Patchell 3
Pens: L Williams 2
Red Card: S Evans
Scarlets: James Davies
