Victory over the Scarlets saw Leinster become the first team to combine European Champions Cup success with the Pro14 title.
Munster came within striking distance of upsetting European champions Leinster, but the hosts hung on to reach the Pro14 final.
Leinster were playing catch-up in Saturday's European Champions Cup final against Racing 92 until the last couple of minutes.
Just as they did in 2009, 2011 and 2012, Leinster tasted European Champions Cup glory as Racing 92's stern resistance proved in vain.
A hamstring injury has cruelly denied Dan Carter a role in Racing 92's European Champions Cup final against Leinster.
Racing 92 stand between Leinster and a record-equalling fourth European Champions Cup win, which is Johnny Sexton's sole focus.
Leinster and Racing 92 will battle it out for European Rugby Champions Cup glory in Bilbao, and we have assessed the best Opta stats.
Fergus McFadden's season is over after the Leinster back damaged his hamstring against Scarlets last month.
Rory Best scored two tries but Ulster's bid to overtake Edinburgh came to an end with a 24-24 draw away to Munster.
Isa Nacewa and Richardt Strauss have been described as "warriors" by Leinster head coach Leo Cullen after announcing they will retire.
Racing 92 were superb for much of their semi-final against Munster, but Laurent Labit says they will have to be even better in the...
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Leinster blew the Scarlets away in Dublin, scoring five tries in a brilliant display to set up a showdown with Racing 92 or...
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Leinster were unable to seal a home semi-final as Benetton Treviso consigned them to a shock home defeat in the Pro14.
Scarlets picked up an impressive win over Glasgow Warriors to keep the pressure on Leinster, while Benetton, Cheetahs and Munster also won.
Leo Cullen felt there were "three or four" occasions where Saracens hit Jonathan Sexton with late shots, but Mark McCall defended his side.
There will be new European Champions Cup winners this year after Leinster dumped Saracens out in Dublin.