Tom James scored inside the first two minutes of the match to get the home side off to a flier while Gareth Cooper scored his first Blues try inside 60 seconds of the second half to send David Young’s side on the way to victory.
James showed some deft footballing skills when toeing the ball ahead when it looked like the ball was going out. His sizzling speed took him past the last line of defence and Tommy Bowe was too late at the scene as the Blues winger scored out wide. Blair’s sideline conversion gave the home side an early 7-0 lead.
Both sides attempted to keep the ball alive with Ospreys full back Barry Davies looking dangerous while flyweight wingers Shane Williams and Leigh Halfpenny were enjoying a ding dong battle out wide.
Blair and Sam Norton-Knight were intent on pegging the Ospreys back with raking kicks while Biggar and Davies repaid the home side with similar tactics.
Both sides showed plenty intent and endeavour but had little to show for it. The Blues increased their lead four minutes from the interval when Steve Tandy was penalised for a high tackle on Jamie Roberts who up until that point had had a quiet game. Blair stepped up and knocked over the penalty with ease to give the Blues a 10-0 lead.
The Blues had an opportunity to extend their lead right on half time but Halfpenny’s long distant shot hit the uprights.
Ryan Jones entered the fray immediately after the break, replacing Steve Tandy, but it was his fellow Welsh backrower Martyn Williams who made an instant impact. Returning from injury, the Blues flanker burst from a maul and sped down the touchline, evading Alun Wyn Jones’s tackle to set up Gareth Cooper for a try inside the first minute of the second half. Once again Blair converted from the touchline to give the Blues a 17-0 lead and a huge mountain to climb for the Ospreys.
The try spurred the Ospreys into action with Williams and Jones taking the game to the Blues but the home side were able to soak up the pressure. Williams’s move to scrumhalf sparked the Ospreys into action. After a couple of darts, the little fella put the Ospreys on the front foot which saw Jerry Collins and Andrew Bishop combine to put Tommy Bowe over in the corner.
Ospreys coach Scott Johnson threw on big guns James Hook, Jonathan Thomas and Nikki Walker in an attempt to gnaw away at the Blues lead but it was to no avail. The Blues took everything the Ospreys threw at them and actually increased their lead three minutes from time when Norton-Knight snapped over a drop goal.
The Ospreys had the last word when Collins battered his way over out wide but it was too little too late as the Blues ran out comfortable victors.
