Leinster will host Connacht at the Aviva Stadium in the second leg of their in their Rugby Champions Cup last 16 on Good Friday, April 15.
A 5.30pm kick-off in the capital will decide which of the Irish sides advances to the quarter-finals in May.
The Sportsground in Galway will be the venue for the first leg seven days earlier (kick-off 8pm) as the provinces get back up to speed following the Six Nations.
A new format in the knockout stages will see the ties played over two legs, beginning with an away tie for the seeds Leinster.
The Blues earned seeding for the last 16 with a fourth-placed finish in Pool A following wins home and away against Bath and a record 89-7 home hammering of Montpellier.
Holders Toulouse will welcome Ulster to Stadium de Toulouse on Saturday, April 9 before travelling to Ravenhill for the second leg seven days later on April 16.
Munster face a tough trip to 2020 champions Exeter Chiefs in Sandy Park on Saturday, April 9 (5.30pm kick-off) before hosting the Premiership side at Thomond Park a week later (KO 3pm).
The highest-ranked teams in the pool stages will have home advantage in the quarter-finals, with the winner of Leinster and Connacht travelling to Clermont Auvergne or Leicester Tigers.
And the winner of Ulster and Toulouse will host the winner of Munster and Exeter in the quarter-finals to take place on the weekend ending May 8.
