Wales flanker Alun-Wyn Jones grabbed a last-gasp try to give Ospreys a 21-18 victory against Glasgow at Firhill.
Glasgow had produced a stirring comeback and looked on course to foil the Welsh form horses in the Celtic League clash when Thom Evans bagged his second try of the night.
But Jones ploughed over at the other end to leave Sean Lineen's men wallowing in frustration.
Ospreys had made the trek north in the wake of a highly successful week which began when they snatched a crucial away win against stubborn Connacht in Galway, and continued with a clinical demolition job on Cardiff on home turf.
They carried on the momentum in the opening half-hour against a hesitant looking Warriors outfit.
Both teams took a while to settle and most of the early play was confined to the area between the 22 lines.
The quest of the hosts was hindered by an uncharacteristic lapse in kicking form by stand-off Dan Parks.
Parks, who needed just three points to become the highest scorer in Celtic League history, was off the mark with four attempts at goal.
The Welshmen looked the more composed side and it was no surprise when they inched in front with a well-struck penalty by Dan Biggar, deputising in the starting formation for James Hook.
Even better was to come for the visitors when substitute utility back Kristian Philips ploughed over for a try, although Biggar sent the conversion wide.
The spotlight was back on Parks just after the half-hour mark, and this time he was bang on target to get the home team up and running.
His strike steadied his own jitters - and those of his team-mates, and they snatched the initiative on the brink of the break.
Scrum-half Mark McMillan sent a beautifully weighed chip into the danger zone, leaving the Ospreys defence to back-pedal.
Thom Evans anticipated the bounce to perfection and scooped it up to dive over beside the posts, giving Parks a formality of a conversion to put Glasgow in front.
Parks had another chance seconds after the restart with a penalty from well inside his own half, but it dipped short of the crossbar.
Ospreys - and Biggar in particular - made the most of their reprieve.
He reclaimed the lead with a marvellous long-range drop-goal which had even the most faithful of the home fans applauding.
Then he kicked his second penalty after a wayward clearance by Parks.
Parks made amends by landing his second penalty as the Warriors stepped up the pace in the closing stages.
There was added pressure on the Ospreys when Jamie Nutbrown was yellow-carded for a professional foul.
Glasgow capitalised immediately as Evans completed his double, pouncing on a Parks lob.
The conversion by Parks drifted agonisingly wide - leaving the stage clear for Jones to snatch the clincher which Hook converted.