THE Ospreys' recent Pro12 resurgence stalled last night as they were beaten 23-13 by Edinburgh at Murrayfield.
Having won their last five league fixtures, the reigning champions had travelled to Scotland with hopes of lifting themselves into the play-off places for the first time this season.
But a try from Willem Nel and six Gregor Hunter penalties consigned Steve Tandy's men to a fourth Pro12 defeat of the campaign, and gave Edinburgh their first win since September.
What made it all the more galling for the Ospreys was the fact that Hunter's final penalty, the last kick of the game, denied them the consolation of a losing bonus point.
Matthew Morgan scored every Ospreys point as they led 13-8 at half-time, but yellow cards to Owen Williams and Sam Lewis undermined the visitors' second-half effort as Edinburgh ground their way to a deserved victory.
Regional matches taking place during the autumn Tests tend to be low-key affairs, though there was no lack of international presence at Murrayfield.
A third of the Ospreys' players had represented their countries at senior level, while Edinburgh included 63-cap Scotland hooker Ross Ford in their side.
Yet for all the experience in the Ospreys' side, it was their younger charges who asserted themselves most impressively in the early stages.
Lock Lloyd Peers, making his second regional league start having trained with Wales in the week, forced a turnover and stole an Edinburgh line-out inside the first five minutes.
Another tyro, fly-half Morgan, had the first whiff of a try as he intercepted a 13th-minute pass from Stuart McInally, but the pocket dynamo was ankle-tapped by Edinburgh's Richie Rees just as he seemed to be streaking clear.
Morgan did not have to wait much longer to get off the mark as, three minutes later, he struck the game's first points with a penalty.
Tom Isaacs also threatened with a fine hand-off and grubber to the line but, soon after that Ospreys attack was repelled, Edinburgh levelled thanks to a Hunter penalty.
There was no shortage of perseverance from the Ospreys. Shortly before the half-hour mark, they kept possession for a remarkable 27 phases, though all they produced from that period of pressure was another Morgan penalty.
After the attrition of the visiting attack, Edinburgh cut loose to score the opening try.
Following a home line-out near the halfway line, outside centre Dougie Fife made the initial break on the right wing and passed inside to Hunter. The fly-half then found Rees, who flicked the ball to Nel, and the prop cantered over from short range.
Hunter missed the conversion and, just three minutes later, the Ospreys regained the lead.
Rhys Webb set the attack in motion by charging down a Rees clearance, and James King smothered the ball in the Edinburgh 22.
With the hosts scrabbling in defence, Andrew Bishop bore down on the Edinburgh line and, although he was tackled, the centre offloaded to Morgan who scampered over from ten yards.
Morgan converted to give the Ospreys a 13-8 half-time lead, but the second period did not begin well for the visitors.
Debutant prop Williams was sin-binned for repeated infringements, with the yellow card coming after he conceded a second penalty from a scrum.
Nicky Thomas, another front- rower making his first appearance for the Ospreys, temporarily replaced flanker George Stowers, and it was a chastening start for the 18-year-old as he was penalised at his first scrum.
Edinburgh capitalised on Williams's absence, taking a 14-13 lead via two Hunter penalties when the Bridgend prop was sidelined.
With referee David Wilkinson demanding an improvement from both sides at the scrum, the Ospreys brought on the seasoned pairing of prop Duncan Jones and lock Ian Gough.
Despite this introduction of 121 Wales caps, the visitors fell further behind as Hunter struck another two penalties.
Against the run of play, the Ospreys came agonisingly close to hauling themselves back into the tie. Morgan blocked a Hunter clearance and picked up the loose ball in the hosts' 22, but he was held up inches short of the try line.
That attack appeared to galvanise the reigning champions, but their optimism was soon punctured when flanker Lewis was sin-binned for infringing at a ruck.
Edinburgh sensed their opportunity. Having lost their last seven matches, they were not going to let this chance pass lightly.
Leading 20-13 with five minutes left, they pounded on the Ospreys line but squandered a gilt-edged chance as Sep Visser spilled the ball with the visitors' line at his mercy.
That miss was academic, however, as Hunter struck his sixth penalty with the final kick of the game to secure victory for Edinburgh and deny the Ospreys a losing bonus point.