tries from wing hallam amos , replacement nic cudd , a penalty try plus penalties from tom prydie and dorian jones and two prydie conversions brought the dragons back from a big deficit to victory .
scrum-half lloyd williams , fly-half gareth anscombe and number eight josh navidi crossed for the blues , while anscombe added three conversions .
dragons replacement nic cudd powers over for try against cardiff at rodney parade .