Jamal Campbell-Ryce had a hug for each of Barnsley's team rather than a hand-shake in the pre-match line-up. After all he was one of them until his transfer two months ago. But midway through the first half they all wanted to hug him after a free-kick he conceded put the visitors into a 2-1 lead.
There had been a goal for each side in the first three minutes and now Bobby Hassell drove a low ball from the right past a sleepy Bristol defence to set up Daniel Bogdanovic's 14th goal of the season.
Campbell-Ryce had come into City's side at the last minute after Lewin Nyatanga had limped out of the warm-up with an Achilles injury. The diminutive winger is hardly cut out for the wing-back role he had to fill but before the break had fully made up for that free-kick.
Barnsley's defence stopped as he chased a hopeless looking ball to the byline and turned it back for Nicky Maynard to head City level.
It was a decisive moment for City went on to dominate the scoring in the second half in a major boost for caretaker boss Keith Millen who has yet to decide whether to apply for the job vacated last week by Gary Johnson.
The first of the eight goals came inside the first minute with a text-book header from Danny Haynes quickly cancelled out by a half-volley from Hugo Colace.
Scotland international Paul Hartley won the midfield for City after the break as a header from Maynard and roll-in by Haynes from Maynard's squared ball pointed the home side towards a double over the South Yorkshire club.
Maynard would have completed his hat-trick but for an incredible miss almost on the goal-line but, with a quarter-of-an-hour left was brought down by Ryan Shotton for an undisputed penalty driven in by Hartley.
Spirited Barnsley pulled back a late goal with sub Andy Gray steering in a Colace cross and then came close to reducing the margin to a single goal.