He changed the quarter-final against Clermont and the game changed a lot when he came on against Munster.
It also meant that Leo Cullen, who won the European Cup three times as a Leinster player, became the first person to lift the trophy both as player and as coach.
Racing had the chance to equalise from a drop goal at the death but Talès missed his shot and Leinster took the title.
Pat Lambie then sustained a knee injury in the second minute, so French worldwide Tales, who did not feature on the team list in the morning, had to deputise.
Lambie was also the designated place-kicker, after scrum-half Maxime Machenaud was ruled out through injury in recent weeks, and was consoled by former Ireland global Donnacha Ryan as he left the field.
Scott, Day remain in contention at PLAYERS Championship
It was the only blemish in a course-record equalling round that included an eagle at the second hole and nine birdies . The LPGA Tour was founded in 1950 and the senior members of the Champions Tour initially got things going in 1980.
Man City want Aguero and Sterling to stay, insists Pep Guardiola
They worked from day one to the last one, training with us and in the locker room. And Guardiola believes he is an ideal fit for the way City play.
Nadal's record clay run ends in Madrid
With the match balanced one set each, Edmund crucially saved three break points before taking the crucial break in the final set. In Nadal's win over Diego Schwartzman on Wednesday, he broke John McEnroe's record of 49 straight sets won on one surface.
The Irish province's veteran New Zealand-born captain Nacewa, who retires at the end of the season, broke the line, but the winger capped once by Fiji was hauled back by opposite number Teddy Thomas.
Leinster kick off against Racing in Bilbao at 5:45pm on Saturday evening.
"He still a world-class player who will be keen to make an impact when he does come on".
But Sexton responded with a penalty and Iribaren's fourth penalty was cancelled out by Nacewa's boot.
Sexton badly fluffed a long-range effort as Leinster, for all their territorial dominance, couldn't quite find their rhythm amid Racing's desperate, hard-hitting defence.
The sides were level 6-6 at the break.