Two tries were not enough as Gareth Anscombe kicked 18-points to boot the Ospreys to a slender United Rugby Championship victory in Swansea.
Wings Josh Adams and Owen Lane crossed either side of the interval but the 100 per cent kicking of former fans favourite Anscombe punished Cardiff’s indiscipline and lack of accuracy.
It was a disappointing result for the Blue and Blacks, who appeared the most dangerous team but could not get a foothold in the game.
They welcome South African opposition for back-to-back league games at Cardiff Arms Park, with Vodacom Bulls and Cell C Sharks set to visit the capital over the next fortnight.
It took the Ospreys just two minutes to open the scoring with Gareth Anscombe landing a penalty from the half-way line.
With the Ospreys getting the better of the set-piece, the hosts had the greater stability to play off but it was the Cardiff back line that appeared most dangerous.
They caused the Ospreys problems on three occasions in the wide channels but they were unable to capitalise with accuracy lacking in the final stages.
Anscombe landed a second penalty after replays showed Seb Davies’ thunderous hit on Rhys Webb was ever so marginally early.
Priestland had the opportunity to respond on 18 minutes but his long-range penalty hit the left up right. Fortunately though, the ball stayed in play and perhaps unsurprisingly the quickest to react was Adams who crossed on his first appearance since the Lions tour, as Owen Watkin was left flat footed.
The fly-half was on target to nudge his side ahead but Cardiff were dealt a blow when Tomos Williams was sent to the sin-bin for a no arms tackle.
Anscombe stepped up to restore the Ospreys’ lead but it was soon 14 versus 14 as Michael Collins joined Williams on the naughty step. Hallam Amos had embarked on the counter and drew both Collins and Matt Protheroe but his passed was slapped in the tackle by the former.
Anscombe kept the scoreboard ticking and half time approached with the Swansea-based club leading 12-7.
There was a frantic finale to the second-half with both sides enjoying opportunities, which could have led to scores. It ended with the Ospreys backing their pack and kicking a penalty into the 22 but the Cardiff maul defence held strong and earned a turnover scrum.
Cardiff made the perfect start to the second-half as they returned with direct intent and won an early scrum penalty with Rhys Carré receiving the plaudits.
Priestland turned down the shot at goal and kicked to the corner and the decision was vindicated as Owen Lane powered over for a third try in two games.
Turnbull, Matthew Screech and James Ratti all made the hard yards before Carré showed a pair of hands any fly-half would be proud of to put his former housemate away.
Priestland made no mistake from the touchline but the lead continued to change hands as Anscombe slotted a fifth penalty after Rhys Webb milked a generous penalty.
The Ospreys continued to benefit from an edge up front, which increasingly led to penalties and a fine kick from Anscombe put them in the red zone. They hammered at the try-line and Morgan Morris powered over but there was a collective sigh of relief across the Cardiff bench as he lost possession in the process.
Anscombe stretched the Ospreys’ lead and his personal tally to 18 shortly after the hour mark
There were late opportunities for the visitors, but a couple of handling in the Ospreys 22 means they couldn't find the all-important breakthrough late on.