Alun Wyn Jones scores only try as Ospreys edge past Cardiff Blues
A try from skipper Alun Wyn Jones helped Ospreys come from behind to win the Guinness PRO12 derby clash against Cardiff Blues at a rain-lashed Liberty Stadium.
Blues, who claimed a losing bonus point in the 13-6 defeat but have not won in Swansea since 2005, were leading 6-0 through two Jarrod Evans penalties before Jones squeezed over.
Sam Davies, having replaced an injured Dan Biggar at half-time, capped an influential performance with eight points with the boot.
Ospreys went into the game without Wales front-row forwards Paul James (calf) and Scott Baldwin (shoulder) as well as Fiji centre Josh Matavesi, who failed to pass a head injury assessment.
Blues hooker Matthew Rees was suspended while fly-half Rhys Patchell has not recovered from concussion.
Evans, 19, came in for his first PRO12 start for the Blues in place of Patchell and scored the only points of the first half with a seventh-minute penalty after the Ospreys were penalised for not releasing at a ruck.
But though Blues led 3-0 at the interval in rainy and blustery conditions Ospreys had the better of the territory in the first 40 minutes.
Blues suffered a major blow when Wales captain Sam Warburton left the field with an ankle injury in the 32nd minute b ut they finished the half the stronger and would have doubled their lead two minutes from time had fly-half Evans not missed with his second penalty attempt.
Ospreys started the second half without Biggar, who was replaced by Davies, and he had an immediate impact with a series of kicks to the corner and missed a 42nd-minute penalty.
Evans boosted Blues' chances with a near 50-metre penalty after 50 minutes but after that it was all Ospreys as Jones got the ball on the tryline by the posts for a converted try.
And from then on in Ospreys played territorial tactics with Davies kicking penalties on 70 and 78 minutes.