They take on Levadia Tallinn & Dudelange, respectively.
Dundalk and Bohemians are both in action in the second round of qualifying for the Europa Conference League later.
Advancing to round three would bring with it a prize money boost of around half-a-million Euro to the clubs.
Bohemians are away to Dudelange for the first leg of their tie, where there's a half-five kick-off in Luxembourg.
Gypsies' striker Georgie Kelly goes into the game in a great run of form, having scored 11 goals in his last ten games.
One-thousand fans will be in attendance in Tallaght Stadium when Dundalk host Levadia Tallinn at 8pm.
Tallinn arrive to Dublin with a squad which boasts nine Estonian internationals and Dundalk boss Vinny Perth says it feels like a "real European tie".
More Europa Conference League action in play today! 🤗— UEFA Europa Conference League (@EuropaConLeague) July 22, 2021
Feyenoord, FC Basel, Copenhagen, Molde, Gent and Hibernian all in action & fighting to get themselves through to the 3rd round⚽️🏟#UECL #EuropaConferenceLeague pic.twitter.com/eNZCGVMITD