A try in the final minute from lock Alun Wyn Jones saw the Ospreys take their third Magners League win in three games in seven days, with a 21-18 result over Glasgow at Firhill on Friday.
A try in the final minute from lock Alun Wyn Jones saw the Ospreys take their third Magners League win in three games in seven days, with a 21 -18 result over Glasgow at Firhill on Friday.
The Warriors had looked on course for a narrow win against the visiting side when Thom Evans bagged his second try of the night.
But Alun-Wyn 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 Magners 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 the Warriors snatched the initiative on the brink of the break.
Scrum-half Mark McMillan sent a beautifully weighed chip into the danger zone, where 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.
The scorers:
For Glasgow:
Tries: Evans 2
Con: Parks
Pens: Parks 2
For the Ospreys:
Tries: Phillips, Wyn Jones
Con: Hook
Pens: Biggar 2
Drop goal: Biggar
Glasgow: 15 Bernardo Stortoni, 14 Lome Fa'atau, 13 Max Evans, 12 Graeme Morrison, 11 Thom Evans, 10 Dan Parks, 9 Mark McMillan, 8 Johnnie Beattie, 7 John Barclay, 6 Kelly Brown, 5 Alastair Kellock (c), 4 Tim Barker, 3 Moray Low, 2 Dougie Hall, 1 Justin Va'a.
Replacements: 16 Eric Milligan, 17 Kevin Tkachuk, 18 Opeta Palepoi, 19 Stevie Swindall, 20 Colin Gregor, 21 Andrew Henderson, 22 Ruaridh Jackson.
Ospreys: 15 Gareth Owen, 14 Johnny Vaughton, 13 David Bishop, 12 Andrew Bishop, 11 Nikki Walker, 10 Daniel Biggar, 9 Jamie Nutbrown, 8 Filo Tiatia, 7 Marty Holah, 6 Tom Smith, 5 Alun Wyn Jones, 4 Ian Gough, 3 Cai Griffiths, 2 Ed Shervington, 1 Paul James (c).
Replacements: 16 Huw Bennett, 17 Duncan Jones, 18 Andy Lloyd, 19 Jonathan Thomas, 20 Rhys Webb, 21 James Hook, 22 Kristian Phillips.
Referee: Carlo Damasco (Italy)
Assistant Referees: Stefano Penne (Italy), Ronnie Dumma (Scotland)