As Bristol City's defence evaporated before them Cardiff scored three goals in five minutes with home players lining up to be blamed for unintended assists.
It all began with a mix-up between goalkeeper Dean Gerken and centre-back Liam Fontaine which left the net undefended. It was the 19th minute and Peter Whittingham was there to steer home his 18th goal of the season.
If that was unexpected after Bristol City had been applying all the pressure, the others came gift-wrapped.
With Michael Chopra running at the back line the usually secure Louis Carey mis-kicked to let in Ross McCormack for the second goal four minutes after the first.
The inquest was still going on when McCormack then pushed a lovely throughball to Chopra who produced a brilliant finish with the outside of the boot into the bottom right-hand corner.
This was the third meeting between the clubs in a fortnight and Bristol City had freshened up their team with two signings, Jamal Campbell-Ryce who was bought from Barnsley and Patrick Agyemang, borrowed from QPR.
Manager Gary Johnson was encouraged into using an attacking 4-4-2 formation after writing in the programme that this match was very important for his hopes of a play-off place.
Only seconds before Cardiff's goal burst Nicky Maynard had seen a 25-yard shot drift wide of the right-hand post. It was a rare moment for Bristol City as Chopra, Whittingham and McCormack destroyed them.
By half-time Cardiff led 4-0 thanks to an own goal by Fontaine under pressure from Chopra.
The Welsh side famously threw away a similar lead at Peterborough United last month but any home hopes of a similar revival were soon extinguished.
Chopra and McCormack scored another goal apiece within ten minutes of the restart as Cardiff stormed to their biggest win in 80 games between these Severn side rivals.