GUTTED Glasgow Warriors coach Sean Lineen bemoaned his side's bad luck as their Magners League play-off hopes fizzled out in Swansea.
A controversial try for Shane Williams and a second half James Hook score did the damage as Glasgow fought hard but just lacked a cutting edge at the Liberty Stadium.
Lineen said afterwards: "We didn't get the rub of the green anywhere, which was very frustrating.
"Perhaps we did not play enough territory and we played a bit too much in the final third when we just needed to put it in the corners.
"The Ospreys' two tries came from turnovers and that's how they get their momentum."
The first questionable moment arrived early on when Ospreys wing Williams danced down the touchline - too close to the line for some in the Glasgow camp - from halfway to open the scoring following a heavy tackle from Hook which dispossessed Fergus Thomson.
Tempers flared soon after when Rob Dewey clashed with Marty Holah off the ball - earning both players a stern warning from referee George Clancy.
Normally reliable Dan Parks missed two penalty attempts before Glasgow pulled the score back to 7-5 just after the break.
Thomson benefitted when Holah misjudged a line-out and tapped it back into Mark McMillan's possession. McMillan returned to hooker Thomson and he made no mistake in racing over. Unfortunately Parks missed his kick again as Lineen's men looked to draw level.
And it was to prove costly as the Welshmen soon edged themselves further ahead.
Dan Biggar kicked a long-distance penalty to move them four points clear and, soon after, Hook stole away to score his side's second try following a ruck.
Hefin O'Hare was introduced to replace Rob Dewey and his creative play made a few opening but Glasgow were unable to capitalise and Biggar's late penalty settled the scoring.
Ospreys coach Sean Holley said: "I thought we deserved it. Ffair play to the boys, they dug in and got the win."