The battling Blues secured a come-from-behind win thanks to quick-fire tries from Ceri Sweeney and Gavin Evans in the second-half.

The Dragons opened up an 8-0 lead after 19 minutes when Ben Castle broke through for a try to add to James Arlidge’s earlier penalty.

But they had to settle for a losing bonus point as a ten-point kicking haul from Ben Blair helped Cardiff to their seventh successive away win in all competitions.

Blair kicked his first penalty on the half-hour to reduce the deficit and the scored stayed this way until he got his second on 54 minutes to bring the scores to 8-6.

The crucial scores for Cardiff came after 60 and 62 minutes when Sweeney and Evans made the line in quick succession, with Blair converting both efforts.

Dragons full-back Martyn Thomas failed to gather Sweeney’s high kick and the fly-half gathered to beat two more defenders for Blair to convert.

That 60th-minute try was followed from the restart by a spectacular effort, Leigh Halfpenny's breath-taking touchline run ending with replacement centre Evans crossing for Blair to convert once more.

Dragons captain Tom Willis and Cardiff prop Rhys Thomas were sin-binned for brawling and the hosts fought their way to a late losing bonus point as Arlidge knocked over two penalties.

And after seeing their play-off hopes dashed, Dragons boss Paul Turner said: “I’m a little bit despondent.

“A couple of decisions went well against us - in the first half with advantage over - really killed us and the bust up the middle in the second half which was a yellow card and a possible try under the sticks and everybody in the ground saw it and the officials and two touch judges just missed it.

“So they were crucial moments and one of Ceri famous slices has gone and killed us.

“But in fairness we didn't clear our lines well enough in that crucial period in the first 20 minutes of the second half.

“We had ample opportunities to do that and we've come up short on that. The game went from us in a crucial five-minute period.”