City dug out an ugly victory in front of their own fans to extend their lead at the top of Sky Bet League One to eight points.
Far from their best throughout the 90 minutes, Aaron Wilbraham struck the decisive blow with a brilliantly taken header from a 14th minute Luke Freeman corner.
It was a rare piece of quality in a match starved of invention, but Frank Fielding stood firm when called upon to record a significant clean sheet against his former club, not least in tipping one Peter Vincenti header away from goal early in the second half.
Steve Cotterill named an unchanged starting line-up following the 3-1 victory at Doncaster Rovers in midweek, with Matt Smith again among the substitutes for the last game of his loan spell from Fulham.
Visitors Rochdale arrived at Ashton Gate as the division’s highest scorers on the road and were not afraid to take the game to the league leaders from the off.
It was Dale who enjoyed the first notable chance, as 13-goal striker Ian Henderson just could not climb high enough to keep Michael Rose’s left-wing cross down and on target.
City’s next close shave was hardly a good enough opportunity to be considered a chance, as Vincenti tried his luck from 30 yards with an ambitious free kick.
But it was almost struck to perfection, as Vincenti’s curling shot beat Fielding high to his right only to be repelled by the angle of post and bar.
City were on the back foot, but responded through a typically energetic Mark Little burst which almost created an opening for Kieran Agard, before the striker forced debutant Jamie Jones in the Rochdale goal into a first save at his near post.
It was a first glimpse of City’s attacking threat, but before Rochdale could properly compose themselves they were 1-0 down, as Freeman fizzed in the resulting corner at a rate of knots for Wilbraham to power home a stunning header.
But the goal did little to stem the flow of a first half Rochdale had probably shaded.
Vincenti should have equalised on 25 minutes when Jamie Allen tiptoed into a shooting position and forced Fielding to parry the ball straight to Vincenti, who only succeeded in driving the follow-up into the ground and up over the crossbar in trying to keep it down.
It was the visitors’ best chance to find the goal they had threatened, but from then on City were rarely troubled for the remainder of the half as the contest lost much of its early zip.
But still Rochdale continued to press after the restart. Korey Smith saw a shot blocked for the hosts before Fielding was called into action to make another important stop.
When Ashley Eastham clipped the ball over the top, Vincenti still had plenty to do as he thrust his neck muscles to meet it with a powerful header back across the City keeper, who produced a fine save diving to his left to keep the midfielder at bay.
In truth it was an isolated opening of a disjointed second period in which neither side could establish any sort of rhythm.
Vincenti tried latching on to a similar ball 13 minutes later but was again guilty of striking the ball into the ground, allowing Fielding time to make a stooping save down by his near post.
Meanwhile, Henderson was getting closer to adding to his tally for the season, sending one long-range drive a couple of yards wide before glancing a Tom Kennedy cross beyond the far post.
City had been a long way below their best but were displaying the sort of grit and determination required to dig out three more priceless points.
In a funny sort of way, it was a performance of champions.