The Blues won their fifth consecutive Celtic League match to keep their title ambitions on track in a feisty and wet game at Rodney Parade.
Dragons: (10) 13:
Blues: (13) 18:
Tries: Phillips, Czekaj
The in-form visitors struck immediately with Mike Phillips racing over the line after an 89-metre counter-attack.
The Dragons hit back when Michael Owen, who was sin-binned before half-time, drove over for an opportunist try.
But the Blues, who lost Robert Sidoli to the sin-bin, had the last laugh with Chris Czekaj scoring on the overlap.
It was a controlled and disciplined display by the resurgent Blues and a rare home defeat for the disappointing Dragons, whose hopes of qualifying for the Heineken Cup are fading fast.
Dragons coach Paul Turner:
"It was one of those nights when we were never in control of the game."
Blues coach David Young:
"The result keeps us on a roll and it was due reward for our guts and determination."
Dragons: Aled Thomas; Gareth Wyatt, Jon Bryant, Ceri Sweeney, Nathan Brew; Craig Warlow, Gareth Baber; Adam Black, Andrew Brown, Rhys Thomas, Ian Gough, Luke Charteris, Jamie Ringer, Jason Forster (capt), Michael Owen.
Replacements: Steve Jones, David Maddocks, Gethin Robinson, Peter Sidoli, Andrew Hall, Ben Breeze, James Ireland.
Blues: Rhys Williams (capt); Chris Czekaj, Marc Stcherbina, Tristan Davies, Craig Morgan; Nick Robinson, Mike Phillips; John Yapp, Rhys Thomas, Gethin Jenkins, Deiniol Jones, Rob Sidoli, Kort Schubert, Martyn Williams, Xavier Rush.
Replacements: Scott Roberts, Duane Goodfield, Mark Lewis, Robin Sowden-Taylor, Ryan Powell, Nick Macleod, Lee Thomas.
Referee: Nigel Whitehouse (WRU)
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