The Ospreys put up a brave fight after second row Ian Evans received a red card in the 20th minute to leave the Welsh region facing three quarters of the match a man down in numbers. The Ospreys held Leinster to a 17- 3 lead at the break but the floodgates opened in the second half to leave the Ospreys bottom of Pool 1 to complete another miserable campaign.
The Ospreys began the match already out of the tournament after four defeats from five matches. They made three changes in the pack from the side beaten at home by Northampton last weekend, with Adam Jones chosen ahead of Aaron Jarvis at tighthead prop while Tyler Ardron and Ryan Jones replaced Sam Lewis and Joe Bearman in the back row.
Sam Davies came in for Richard Fussell at full-back and Ben John replaced Tom Isaacs in the centre.
Leinster began the match four points clear of Northampton in the pool after grinding out a 29-22 win against Castres in France last weekend.
The Ospreys looked as though they were determined to finish their disappointing campaign on a high and took the game to Leinster early on.
Fly halves Jimmy Gopperth and Dan Biggar exchanged penalties in an evenly contested opening quarter but the odds of an Ospreys win suffered a severe blow when Evans departed the scene for injudicious use of the boot on his opposite number Mike McCarthy, who played no further part in the game.
The home side bided their time before a double strike before halftime saw Leinster firmly in control at the break.
First Leinster’s juggernaut pack, with Cian Healy and Jamie Heaslip firmly in control at the rear, steam rolled towards the Ospreys try-line from a rolling maul with referee Romain Poite awarding a penalty try after the Welsh side brought the maul down illegally.
Leinster then grabbed the game by the scruff of the neck when super charged prop Healy powered his way over two minutes from halftime. With Gopperth adding both conversions Leinster were in control of both the game and the group with a 17-3 lead.
A gutsy defensive effort by the Ospreys frustrated Leinster until the 63rd minute when Poite headed under the posts for the second penalty try of the evening after the Ospreys scrum buckled in a heap over the Welsh try-line.
The bonus point score came via Jordi Murphy in the 73rd minute and by the time replacement scrum half Isaac Boss raced over two minutes later, the shell shocked Ospreys defence was riddled with holes to leave the Irish side cruising through to another quarter-final while the Ospreys were left licking their wounds once again in Europe.
