The Ospreys got 2019 off to a winning start, tries from Scott Williams and George North in the first half and 10 points from Sam Davies securing a second derby win of the festive season.
With barely a minute played the Ospreys had to make a change in the pack, Adam Beard leaving the action on a stretcher after lengthy treatment after he took a bang at an early ruck, Lloyd Ashley replacing him in the engine room.
Despite the change, the Ospreys made the most of early possession to take the lead in the 4th minute. It was Scott Williams who struck for his first try in an Ospreys shirt. It came from a lineout, Sam Davies using a Blues offence on halfway to put his team in the corner, the centre stepping inside and leaving Josh Navidi grasping thin air.
Davies converted, but the visitors struck back almost instantly. Unspotted blocking in midfield allowed Matthew Morgan and Blaine Scully to make 60m between them, only an incredible effort by Alun Wyn Jones stopping the initial surge five metres from the line. However, the ball was quickly recycled and Gareth Anscombe delivered a pinpoint crosskick to the corner to give Garyn Smith a simple finish.
The angle of the conversion proved too much for Anscombe so the Ospreys led 7-5 with under eight minutes played.
The Ospreys were enjoying the lion’s share of possession and territory, probing for a way through and they struck for try number two at the midway point of the half, Davies spotting acres of space behind the defensive line to put a lovely kick to the corner that gave George North the simplest of finishes.
Davies then slotted the conversion and it was a landmark two points for him as he leapfrogged Gavin Henson to go third in the region’s all time points scoring list with only James Hook and Dan Biggar ahead of him.
The final 10 minutes of the half were played out exclusively in Ospreys territory, the visitors unable to find a way through well organised and resolute defence, having to settle for a shot at goal from Anscombe with time up, Ospreys penalised for a high tackle on the 22.
HALF-TIME: OSPREYS 14-8 CARDIFF BLUES 8
A penalty against Navidi, not rolling away, gave Davies what looked a straightforward enough kick from 25m out shortly after the restart but he failed to find the target.
It was all being played in the Blues half and the pressure led to another penalty on 50 minutes, the visitors offside, and this time Davies made no mistake, his kick taking the Ospreys nine clear.
Anscombe then responded in kind after the officials spotted an apparent infringement on the Blues 10 by North.
As the clock ticked down, the Ospreys were on top without really looking like adding to their try tally, and they made the game secure in the last minute, taking away the Blues’ losing bonus point through a Davies drop goal.