Macauley Cook surged over for the winning try as Cardiff Blues came out on top 21-13 in an all-Welsh LV= Cup tussle with Ospreys.
The Blues, who were on the losing end for the majority of the second half, left it until the 74th minute to seal the victory, adding to an earlier Kristian Dacey try, while Simon Humberstone collected 11 points with his boot.
Ospreys centre Jonathan Spratt ran over in the first half while Matthew Morgan also notched two penalties and a conversion, but the hosts could not put any points on the scoreboard after the interval.
Former Harlequins academy player Humberstone was given the nod at fly-half for his first Blues start after impressing from the bench in defeat to Worcester Warriors last week.
And it was the 26-year-old who drew first blood at the Liberty Stadium with eight minutes gone, firing a penalty between the posts.
His opposite number Morgan had the opportunity to level the scores up almost immediately but the 21-year-old saw his kick rattle the post and out.
On the quarter-mark Humberstone struck again off the kicking tee, the Ospreys struggling to issue a response from their LV= Cup opening loss to Leicester Tigers.
However, the home side were offered a spark by Morgan, who nearly broke the whitewash after a scintillating run – and a subsequent penalty kick made sure the 21-year-old was rewarded for his efforts.
But the Blues extended their lead further when hooker Dacey piled over for a 25th-minute try, before Humberstone was off-target with the conversion.
Ospreys fought back and it was via the boot of Morgan again, though the fly-half needed two bites of the cherry within two minutes to drill over his second penalty of the night.
And just before the break the hosts’ captain Spratt finished off a superb solo effort after intercepting Chris Czekaj’s wayward pass.
Morgan added the extras to complete the turnaround but it was a case of backs to the wall for Steve Tandy’s side early in the second half as Cardiff probed.
Impressive scrummaging formed the bedrock of Ospreys’ game and, having soaked up the pressure, they counter-attacked only for Morgan to skew a penalty wide.
In a boost for the home side, scrum-half Rhys Webb appeared off the bench – replacing Tito Tebaldi – to mark his first game back following sixth months out with cruciate ligament damage.
With the score at 13-11 it was anyone’s game to take by the scruff of the neck but both sides continue to struggle working the ball within sight of the try-line.
But the breakthrough finally arrived on 74 minutes through Cook, while Humberstone – following a successful conversion – put the game to bed with a drop-goal at the death.
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