Eli Walker scored his side's only try, rounding off a wonderful run from Richard Fussell, and Matthew Morgan added 12 points with his boot, to round off a memorable weekend at the Liberty Stadium that has seen the Swans holding football's European champs Chelsea on Saturday, a day before the Ospreys went one better and sent rugby's Euro kings home with nothing.

An early decision against George Stowers allowed Leinster to make the first mark on the scoreboard, Ian Madigan slotting over a penalty in just the fourth minute.

Leinster then had the Ospreys on the backfoot, Isaac Boss spotting acres of space behind the Ospreys defensive line, allowing Fion Carr to chase, and although he won the race to gather just short of the line he was unable to stay in play.

They kept the pressure on though, Rhys Webb's attempted clearance from the resulting lineout charged down by Rhys Ruddock on his own line and as players scrambled to gather the loose ball, number eight Leo Auva'a was able to dab down. There was more than a suspicion of a knock-on before he grounded, and the TMO took an age to make his mind up before finally awarding the score, Madigan adding the extras to make it 10-0 with just nine minutes on the clock.

The Ospreys had yet to enjoy much territory or possession, but a Morgan up and under left the Leinster defence in disarray, the ball eventually reaching George Stowers on the wing, the big Samoan being bundled into touch just short.

Morgan was then able to get the Ospreys on the scoreboard with a penalty after quarter of an hour after a Leinster tackler was penalised for not releasing.

Buoyed by the score the Ospreys worked their way upfield through the forwards, taking turns to make the hard yards with a series of pick and drives before eventually winning a penalty, which Morgan was able to slot over.

The rain was hammering down by now, with players on both sides having real difficulty to retain the ball at times. Andrew Conway almost managed to find his way through in the corner after a good break from Boss, Carr's little dink through bouncing awkwardly which meant the covering Walker was happy to hack it clear as Conway looked to pounce.

Leinster were able to maintain the pressure, and an offside decision against Lloyd Peers allowed Madigan another seemingly straightforward pop at goal but he sliced it horribly wide.

At the other end, some great play from the Ospreys front eight at a maul was rewarded with a penalty, allowing Morgan to add another three points, leaving the Ospreys trailing by just one point at the interval.

HALF-TIME: OSPREYS 9 LEINSTER 10

The Ospreys thought they'd got the perfect start to the second half, with a try inside two minutes of the restart, only for referee John Lacey to anger the crowd on two fronts.

Richard Fussell's grubber to the corner gave Eli Walker something to chase, only for the wing to clearly be tackled without the ball. As it bounced loose, Fussell grounded, only for Mr Lacey to bring play back for an alleged knock-on by Walker.

Morgan then failed with a penalty from the left that would have put his team ahead for the first time, before Madigan's long range effort from the halfway line just dropped below the crossbar, after Duncan Jones had been pinged - and yellow carded - for a side entry.

Only a last gasp tackle from Webb prevented Carr going all the way through after a sidestepping run had seen him scythe through the Ospreys defence, the scrumhalf eventually bringing him down just a couple of metres out.

A man light and with Andrew Bishop packing down at openside the Ospreys were able to survive a Leinster 5m scrum, Joe Bearman epitomising the spirit in the camp as he drove Auva'a back 10m as the Leinster try-scorer tried to pick up at the base and go for the line, much to the delight of the home crowd.

As the clock reached the hour, and with Duncan stood on the touchline waiting to return to the action, the Ospreys snatched the initiative with a wonderful try launched from deep inside their own territory.

Morgan launched a quickly taken lineout to Fussell who set off on a tremendous run upfield, leaving the Leinster defence for dead, and with a two-man overlap he fed a simple pass to Walker who raced over to score. Morgan's conversion put the Ospreys six points clear with a quarter of the game remaining.

Walker was almost put through again, the Ospreys stealing a Leinster lineout and spreading it wide, but Fussell's grubber bounced the wrong way, going out of play when the winger was hoping it would stay infield to give him a simple run-in.

However, with Leinster looking to run their way out from the back they played themselves in to trouble, and with the Ospreys winning possession, Morgan slotted over a drop goal to take his team nine clear.

With the biggest crowd of the season making themselves heard the Ospreys found themselves under pressure in the closing minutes as Leinster tried to get the score that would gave them a losing bonus point but solid defence ensure they left the Liberty empty handed, the hosts recording a fifth straight PRO12 win.