Garry Ringrose, who has long been touted as a future Ireland international, shone in a man-of-the-match performance - but other youngsters impressed.
Cian Kelleher and Adam Byrne scored their first GUINNESS PRO12 tries for the Irish province, while the likes of Peter Dooley and Dan Leavy also proved their worth from the bench. Luke McGrath, who has just turned 23, also provided a spark off the bench from scrum-half.
Their collective efforts helped Leinster, who are a point behind leaders Ulster with a game in hand, up to third and Cullen says fringe players have certainly put their hands up for this weekend's clash with Cardiff Blues.
"Conceding nothing is always pleasing as well, so Girvan (Dempsey) and Kurt (McQuilkin) will be quite happy," Cullen said.
"You want guys to come in and make an impact, you want guys to be pushing for a place in the team. It's a really good window for players to showcase their talents.
"Some guys we wouldn't have seen a huge amount of so far and it's pleasing to see some of those guys come off the bench and make a real impact.
"The bonus point is crucially important, we threw one away the last day against Dragons and those points make a huge amount of difference in the shake-up later in the season."
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