It was a tough evening for a young Ospreys line-up as they put in a shift full of endeavour and spirit but were unable to prevent Wasps taking the spoils in the Liberty Stadium rain.
The visitors raced into a 19-0 lead inside the opening 20 minutes before the Ospreys hit back through first tries for Reuben Morgan-Williams and Ifan Phillips to trail by just seven at the break.
The second half saw Wasps pull away from their hosts despite some bright moments for the home team.
After a lively opening eight minutes or so, both sides playing with positive intent, it was Wasps who grabbed the first try, hooker Antonio Harris with a simple finish from a lineout deep inside the Ospreys 22 for a score that went unconverted.
The home team were back under their own posts inside a minute, the experienced Brendan Macken reading Luke Price’s pass in midfield to intercept on the Ospreys 10m line and race through between the sticks unchecked. Connor Eastgate added the simplest of conversions and the visitors were all of a sudden holding a 12-point lead.
Wasps were able to claim a third try before the end of the first quarter, moving the ball across the field, right to left, where they had Guy Armitage over. The winger finished easily before Eastgate added the extras from the touchline.
On more than one occasion the Ospreys had been able to get into a decent position only for their lineout to fail, allowing Wasps to clear. So, with 25 minutes gone, skipper Price opted to tap and go 15m out, feeding Kieran Williams to carry strongly before giving it to Jay Baker who was hauled down agonisingly short of the line.
The visitors strayed offside as the Ospreys pressed and this time the lineout worked, the pack drove forward and with an advantage in their favour it was Morgan-Williams who sniped his way over from close range to score, Price converting.
Buoyed by the breakthrough the Ospreys were immediately looking more confident and some great play between the backs almost sent Baker over in the corner.
As they maintained the pressure Paul Doran Jones was pinged on the floor and shown a yellow card, the Ospreys taking full advantage. They went to the corner, the lineout was effective and Phillips dabbed down after the pack had rumbled forward.
Price missed with the conversion attempt so as the teams headed down the tunnel at the break the visitors led by seven.
HALF-TIME: OSPREYS 12-19 WASPS
The Ospreys would have been looking to start the second as they ended the first but Wasps claimed a fourth try, and a bonus point, within five minutes. It was South Africa international Nizaam Carr scoring after the visitors had turned the screw at an Ospreys scrum on their own line.
Eastgate duly added a third conversion and then followed it with a simple three pointer following an Ospreys offside to move his team 17 clear with half an hour remaining.
A wonderful moment from Jay Baker brought the Liberty to crowd to life, the winger taking advantage of good defensive pressure to pounce on a loose ball inside his 22 before displaying nifty footwork to get past two Wasps players and carry 50m upfield. Morgan-Williams was up in support, carrying into the 22.
The Ospreys were unable to take advantage of an overlap on the left though, rushing things and opting to send a long, looping miss pass to the wing instead of working it through the hands and the chance was gone as the ball went forward.
Wasps came back at the Ospreys and using their scrum as a platform to attack the visitors pressed again, only great last gasp defensive work from Baker and Joe Tomalin-Reeves preventing Jacob Umaga getting the ball down.
The pressure on the Ospreys line continued and Wasps stretched the lead when Macken crashed over the line from close range, Eastgate adding the extra two.
To their credit the young Ospreys refused to throw the towel in and their rolling maul proved effective, marching Wasps backwards towards their own line. Baker used his power to force his way through, only to have what he thought was a try chalked off, the referee ruling correctly that the winger had been tackled before bouncing back to his feet.
With time up on the clock the Ospreys threatened one last time, Phil Jones on an arcing run from half way to put his side into a good position but when the ball was knocked on in the corner to bring the game to a close it summed up a frustrating second 40 for the hosts.