Former Town centre-back Adam Webster has given Bristol City a 1-0 half-time lead, despite the Blues making a promising start to the game.
Boss Paul Lambert made five changes for his side's visit to Bristol with Josh Emmanuel and Toto Nsiala coming into the defence, Trevoh Chalobah and Andre Dozzell starting in midfield, and Kayden Jackson replacing Collin Quaner up front.
Emmanuel made his first Town start since the final day of 2016/17 with loanee James Bree and midfield duo Cole Skuse and Teddy Bishop all dropping to the bench, while there was no place in the matchday squad for either Quaner or Jonas Knudsen.
Young keeper Harry Wright and midfielder Idris El Mizouni, who has impressed at reserve and youth levels this season, were both named on the bench for the first time in their senior careers.
The home side gave a debut to New Zealander Stefan Marinovic in goal, while former Town player Webster, who joined Bristol City in the summer, started at the back.
Inside the first minute, Jackson closed down Marinovic following a routine back-pass and although the Kiwi international had taken too long to clear the ball, following Jackson's block the ball rolled across the area before being hacked away by Lloyd Kelly for an early corner.
The Blues had started well and controlled much of the opening play, and a neat touch from Jon Nolan came close to releasing Jackson but the Town front man was denied by some good defending from the hosts.
In the 10th minute, a wide right free-kick from Alan Judge was only partially cleared by the Robins and the ball fell to Chalobah just inside the box, but his first-time volley was skewed well wide of the target.
Minutes later, Chalobah played the ball out to Gwion Edwards on the right but Jackson was unable to make any meaningful contact with the Welshman's deep cross.
Famara Diedhiou cleared Judge's freekick away for another corner for the Blues which was flicked over by skipper Chambers at the near post, moments before Marinovic did well to get down low to parry away a deflected volley from Judge.
The hosts had their first little spell of pressure with a couple of left-sided corners shortly before the midway point in the first half, the second of which was headed over by Diedhiou.
Dozzell was lucky to avoid a booking after a blatant pull back on Jack Hunt wide on the right and from the resultant freekick, the ball fell kindly to Andreas Weimann and he hit a shot from the corner of the six-yard box which struck the outside of Bartosz Bialkowski's near post.
Nsiala and Edwards then combined to make an important block to deny Weimann, who had cut in and hit a dangerous left-foot shot from close range.
On the half hour mark, Dozzell committed a second rather cynical foul in a matter of minutes - this time on Eliasson on the halfway line - and he received the first caution of the game, and his second of the season.
Two minutes later the home side worked a short corner back to Eliasson and his dangerous ball into the area looped into the air following a deflection off Dozzell's head and Webster beat Nsiala in the air to head home from a couple of yards out.
Half-hearted appeals from Town for a penalty for handball after Judge's long-range effort struck Hunt were waved away by referee Darren Bond, before Diedhiou acrobatically turned Hunt's cross over the bar at the other end.
Marinovic collected and held a 25-yard drive from Edwards, shortly before another dangerous delivery from Eliasson was helped onto the roof of the net by the unmarked Diedhiou.
After a bright first 15 minutes which they again failed to make count in terms of goals, the much-changed Blues had rather faded with the Robins goal another which boss Lambert will feel shouldn’t have been conceded, while Webster being the man to score against his old club had an inevitability about it.
Town: Bialkowski, Emmanuel, Chambers (c), Nsiala, Kenlock, Chalobah, Dozzell, Nolan, Edwards, Judge, Jackson. Subs: Wright, Skuse, Harrison, Bishop, Bree, El Mizouni, Dawkins.
Bristol City: Marinovic, Webster, Brownhill, Diedhou, Weimann, Kelly, Eliasson, Paterson, Pack (c), Kalas, Hunt. Subs: O'Leary, Dasilva, Wright, Taylor, O'Dowda, Semenyo, Palmer. Referee: Darren Bond (Lancashire).