A youthful Ospreys side ran in three tries to see off the challenge of Leeds at the Liberty Stadium on Thursday night.
Hanno Dirksen, Steve Tandy and Jamie Nutbrown touched down for the Ospreys, Tom Prydie converting all three tries, as the region secured their first win in this year's Anglo-Welsh competition at the fourth attempt.
Both sides went into the game sitting bottom of their respective pools and with no chance of progressing to the knockout stage, but as far as the Ospreys were concerned, the match had a vital role to play in the ongoing development of a number of young players who were gaining important exposure to a higher level of rugby.
Among those youngsters were 18 year-old Dirksen of Swansea RFC, and young hooker Marc Breeze, who were making their first starts for the region, while 17-year old Prydie was making only his second start in an Ospreys shirt. There were also three potential debutants among the replacements, 18-year old Bonymaen prop Will Taylor, 18-year old Aberavon centre Ben John and former Ireland U20 second row Conor McInerney who signed for the region from Leinster last summer but has been sidelined with a knee injury.
The visitors were handed the chance to get the first points on the board when Dirksen, playing on the wing, was pinged for straying in front of the kicker, and Leeds fly-half Joe Ford duly obliged with a penalty effort from close to the touchline with 10 minutes gone.
There was almost an instant response, Wales squad member Prydie reading Gareth Owen's clever cross kick from halfway well, taking the ball on the bounce and surging towards the line only to be tackled into a touch a metre short by Leigh Blackett.
The Ospreys did grab the game's first try at the end of the first quarter, Dirksen touching down in the corner for his first Ospreys try. It was the South African born teenager who started the move with a powerful run from inside his own half before slipping the ball inside to Ashley Beck. The Aberavon centre carried well before being brought down close to the line, and as the ball was recycled Dirksen barged his way over from close range, Prydie adding the extras from a testing conversion attempt on the touchline.
Prydie was then unlucky with a long range penalty effort from just inside Leeds territory, the ball striking the left upright.
The Ospreys were enjoying the lions share of territory and possession, and it came as no surprised when they extended their lead just after the half hour following a move that had seen the ball pass through several pairs of hands before Gareth Owen's grubber into a gap behind the Leeds defence, Tandy winning the race to ground it. Prydie's successful conversion made the score 14-3 to the home side.
With halftime approaching, Leeds served a reminder to the young Ospreys side that there was still plenty of work to do if they were to take anything from this game, Erik Lund being driven over from close range after a spell of concerted pressure on the Ospreys tryline, Ford converting.
There was a brief blood change for the Ospreys when Steve Tandy left the field just before the break, Ben Lewis taking his place in the action for just a couple of minutes, Tandy returning before the half-time whistle.
Leeds were enjoying their best spell of the game, and after a promising move that saw them move the ball wide from a central scrum before coming back infield, Ford's drop goal attempt drifted wide to the right, leaving his team trailing by four at the break.
HALF TIME: OSPREYS 14 LEEDS CARNEGIE 10
Twice in the opening minutes of the second period Prydie had the opportunity to extend his team's lead, but both times he failed to convert what seemed like straightforward penalties.
With 50 minutes on the clock, the Ospreys made a permanent switch at openside, Lewis coming on in place of Tandy once again, before Cai Griffiths and Ed Shervington were introduced for Craig Mitchell and Marc Breeze.
The game was being played almost exclusively in the Leeds half at this stage, with the visitors seemingly unable to clear their lines despite enjoying considerable possession, and handling errors from the Ospreys preventing them from being able to turn the screw on their opponents.
The pressure finally told with the third Ospreys try of the night coming after 65 minutes, Jamie Nutbrown spotting a gap from the base of a scrum and bursting through unchecked to score under the posts, Prydie's conversion making it 21-10.
On a rare foray forward, Leeds were ruing their bad luck when referee Gwyn Morris inadvertently got in the way of a promising move after Lee Blackett and Henry Fa'afili had taken their side forward from deep in their own half to almost onto the Ospreys 22, allowing Owen to gather the loose ball and clear the danger, sending the ball back into the Leeds 22.
The Ospreys then made a string of changes, Richard Kelly replacing Andy Lloyd for only his third Ospreys appearance, Rhys Webb for try-scorer Nutbrown, with Ben Johnand Conor McInerney coming on for their debuts in place of Jonny Vaughton and Ian Evans.
As the clock ticked down and Leeds looked for a way back, a powerful burst from Fa'afili saw him carry the ball towards the Ospreys try line before offloading to former Scarlet Ceiron Thomas who was pulled down in the corner, and as the ball was recycled for the visitors, Bevington was penalised for killing the ball, an offence that saw the young prop sent to the sin-bin, a decision which meant that the hosts would play out the final six minutes with just 14 men.
The Ospreys paid the full price for continued indiscipline following the resultant scrum, the referee first playing advantage for an offence in the scrum and then penalising Webb for deliberately interfering with the ball in an offside position, awarding a penalty try, with the simple conversion from Ford making it 21-17.
The tight scoreline didn't really reflect the Ospreys dominance, ensuring a nervy final few minutes, but the Ospreys were able to hold for the win, rounding off their LV= Cup involvement for the season on a positive note.