Despite entering their first-ever European adventure, Oliver Glasner's side are learning at a rapid pace. Missing key figures like striker Jean-Philippe Mateta and defender Daniel Muñoz, the Eagles departed Dublin with a comfortable win that virtually secures them a place in the Europa Conference League qualifying rounds.
Another victory in their next fixture against Finland's KuPS should be sufficient to secure direct passage to the last 16, especially after a previous setback against Strasbourg.
This match offered a platform for some of Palace's lesser-used players to impress. Christantus Uche, in only his second start after arriving on loan from Getafe, notched the scoring with a clinical goal. Forward Eddie Nketiah added a second, scoring for the second consecutive match.
The Shelbourne side that had concluded their domestic season proved no match against a largely second-string Palace outfit. The visitors were further weakened by the news that Mateta and Muñoz are out with leg problems.
In spite of heavy rain in Dublin, Palace quickly took control. A flowing move in the 11th minute, initiated by Daichi Kamada's clever pass, allowed Nketiah to set up Uche for a simple tap-in.
Youngster Adam Wharton went close soon after, driving a powerful shot over the bar. Nketiah then claimed for a penalty after racing into the box, but the official dismissed the appeals.
Ex-Arsenal man didn't need to wait long to find his goal, prodding home from close range after Uche's effort had struck the post.
The home side were clinging on for dear life. Full-back Kameron Ledwidge was fortunate to avoid a booking for two robust challenges on Yeremy Pino, before Chris Richards rattled the crossbar with a header from a corner.
The contest was as good as over eight minutes before half-time. Yeremy Pino meandered past some weak challenges before coolly slotting a shot past goalkeeper Wessel Speel to extend the lead to 3-0.
Following the break, manager Oliver Glasner took the chance to withdraw several individuals like Kamada and Wharton. Substitute Romain Esse came close to scoring his first touch, but saw his shot blocked.
Esse was incredibly unlucky later on, seeing one shot crash off each posts before being gathered on the line. Uche also blazed a glaring chance, showing there is still room for development in his game.
A solitary concern for Palace was a late injury to Justin Devenny, who was forced off. This allowed 17-year-old forward Benji Casey to earn his senior debut, capping an otherwise positive night for the visiting side.