Leinster host the Dragons and Munster face Zebre.
Munster and Leinster are both in Guinness PRO14 Rainbow Cup action later on.
Johann van Graan's side are away to Zebre from 7-o'clock.
None of the four players who sustained burn injuries in a fire pit accident over the weekend - Damian de Allende, R-G Snyman and Mike Haley and C-J Stander - are set to feature.
Then at a quarter-past-8 tonight, Leinster host the Dragons with 1200 fans to go through the gates of the RDS.