Even though entering their maiden continental adventure, Crystal Palace are learning at a rapid pace. Without key figures like striker Jean-Philippe Mateta and defender Daniel Muñoz, the Eagles departed Dublin with a commanding result that virtually secures them a place in the Europa Conference League playoffs.
Another three points in their upcoming match against Finland's KuPS ought to be enough to secure straight entry to the last 16, especially following a previous setback against Strasbourg.
This occasion provided a platform for some of Palace's fringe talent to shine. Christantus Uche, making only his second start after arriving on loan from Getafe, opened the scoring with a well-taken finish. Striker Eddie Nketiah contributed a another, finding the net for the second consecutive match.
A Shelbourne team that had finished their domestic season were outmatched even for a mostly rotated Palace lineup. The Londoners were already depleted by the reports that Mateta and Muñoz are sidelined with leg injuries.
Despite torrential rain in Dublin, Palace rapidly established dominance. A flowing passing sequence in the 11th minute, sparked by Daichi Kamada's incisive pass, allowed Nketiah to lay on Uche for a simple tap-in.
Youngster Adam Wharton came close soon after, driving a long-range effort over the bar. Nketiah subsequently claimed for a penalty after bursting into the box, but the referee dismissed the protests.
Ex-Arsenal striker did not have wait long to get his goal, prodding home from a yard out after Uche's shot had struck the post.
Shelbourne were clinging on desperately. Full-back Kameron Ledwidge was lucky to avoid a booking for a couple of robust tackles on Yeremy Pino, before Chris Richards struck the crossbar with a header from a corner.
The match was effectively over eight minutes from half-time. Yeremy Pino weaved past a series of weak challenges before calmly slotting a shot past keeper Wessel Speel to extend the lead to 3-0.
After the break, manager Oliver Glasner took the chance to rest key players like Kamada and Wharton. Substitute Romain Esse came close to scoring his very first touch, but saw his shot blocked.
Esse was desperately unlucky later on, seeing one shot strike off both posts before being gathered on the line. Uche then blazed a sitter of a chance, indicating there is still scope for improvement in his game.
The only concern for Palace was a second-half knock to Justin Devenny, who limped off. This paved the way for 17-year-old striker Benji Casey to make his first-team debut, rounding off an otherwise positive night for the traveling side.