Leo Cullen’s men took their winning form from pre-season into the opening round of the revamped PRO14, with four second half tries – including one from 20-year-old winger Jordan Larmour – sealing a deserved bonus point.

Jamison Gibson-Park’s 22nd-minute score, coupled with three well-struck kicks from his half-back partner Ross Byrne, had Leinster 13-6 in front at half-time in Newport.

Two Gavin Henson penalties ensured Bernard Jackman’s Dragons still in the hunt, before a penalty try and Larmour’s five-pointer, either side of Matthew Screech’s sin-binning, gave the visitors a match-winning cushion of 25-9.

Dan Leavy and replacement Cathal Marsh added two more converted tries before the finish, taking Leinster’s haul to five in all, but the Dragons did gain some consolation in the form of a penalty try which also saw Adam Byrne yellow carded for a high tackle.

Cullen gave competitive debuts to Larmour, Australian international Scott Fardy and James Ryan, who made his provincial bow off the bench, while captain and man-of-the-match Isa Nacewa featured at centre alongside Rory O’Loughlin, and Max Deegan packed down at number 8 for his first start.

Leinster were quick to settle on Rodney Parade’s new Desso pitch, Adam Byrne threatening on the right wing and the industrious Fardy stealing ball after a big midfield tackle from Nacewa.

Although Dragons debutant Henson overcooked a penalty kick to touch, Leinster were falling foul of Scottish referee Mike Adamson’s whistle and a central penalty allowed Henson to fire the Dragons ahead in the 10th minute.

Henson mixed the good with the bad, kicking the ball dead and then coughing up a penalty which his opposite number Byrne confidently dispatched through the posts, bringing Leinster level by the end of the first quarter.

After Larmour looked dangerous on a kick chase on the left, Leinster retained possession near the hosts’ 22 and Nacewa’s neat step and break had him close to scoring before his pass was intercepted by Cory Hill, who saved a near certain try.

Nonetheless, from the resulting five-metre scrum, a nice angle allowed Kiwi scrum half Gibson-Park to dart off the base and make it over just to the right of the posts. Ross Byrne converted the try for a 10-3 lead.

Leinster’s superior scrum and the influence of the likes of Fardy, Deegan and the returning Rob Kearney around the park were obvious positives, but the Dragons were having more of the ball nearing the half hour. A marginal penalty call against Fardy, who thought he had pinched another turnover, saw Henson hit the target to close the gap back to four points.

Leinster were the aggressors, though, with the interval in sight. O’Loughlin was put through a gap as the Dragons defence gave way, with an eager Cian Healy soon stretching his legs on a surge up to the home 22.

The late bout of possession and territory eventually yielded a penalty – Harrison Keddie infringed at an advancing maul – and the increasingly-influential Byrne split the posts with the last kick of the opening half.

Within two minutes of the restart, Leinster were 20-6 to the good after flying out of the traps. Sean Cronin carried strongly and O’Loughlin gunned for the left corner before the Dragons conceded a five-metre lineout, from which the Leinster maul forced a penalty try. Second row Screech also saw yellow for his infringement.

After Henson punished Dan Leavy for a ruck offence, the visitors conjured up their third try. Healy carried up close before the defence was sucked in, allowing Gibson-Park and Nacewa the time and space to release Larmour for an unconverted effort on the left.

The 14-man Dragons avoided any further concessions before Screech’s return, while the front row trio of Ed Byrne, James Tracy and Andrew Porter were the first players unleashed off Leinster’s strong bench. The reserves made a big impact during the final quarter as the tempo quickened again and the Dragons defence came under intense pressure.

They were taken through a strength-sapping 14 phases which began with a Nacewa turnover in his own 22. Jack Conan’s offload out of a tackle sent James Ryan galloping over halfway. Possession was retained under the direction of Nick McCarthy, and the Welshmen could not hold out as Conan’s outstanding one-handed offload sent Leavy in under the posts with 15 minutes remaining.

With the bonus point in the bag, Leinster sent on their final two replacements in the form of Marsh and Barry Daly. The Dragons responded with some of their best rugby of the day, Tyler Morgan breaking towards the left wing and setting up Ashton Hewitt, who drew a high tackle from the covering Adam Byrne. Consultation with TMO Neil Paterson saw Byrne binned and the hosts awarded a penalty try for 32-16.

Despite their numerical disadvantage, Leinster made sure they had the final say when a Barry Daly interception sparked 10 fast-paced phases deep in the Dragons half and Marsh magically spun out of a tackle and scrambled over the whitewash under a pile of bodies. The try scorer’s conversion made it a 23-point winning margin.

Tickets for Leinster Rugby’s first home game of the new season against Cardiff Blues at the RDS Arena on Friday, 8th September (KO 7.35pm), are on sale now from €20.

Leinster v Cardiff Blues