A remarkable display of resilience saw ten-man City hang on for a third straight victory at the home of promotion-chasing Peterborough United.
All seemed to be going smoothly for the visitors when Sam Baldock, so often the scourge of the London Road club, scored his fifth and sixth goals in just his fourth appearance against Posh since joining the Robins last season.
Two simple finishes from the skipper had the Robins well in control inside the opening 16 minutes, but the dismissal of Adam El-Abd four minutes later for an off-the-ball clash with Britt Assombalonga left City with a huge task on their hands.
The hosts duly halved the deficit at the worst possible time, as Michael Bostwick headed home just before the interval, prompting a second-half siege.
But City, who owed a debt of gratitude to the brilliance of Frank Fielding late on, somehow survived to continue their perfect start to the month.
Steve Cotterill made three changes to his latest winning team, including the return of Scott Wagstaff after five weeks out with a shoulder injury.
There were also recalls for Karleigh Osborne and Greg Cunningham at the expense of Stephen Pearson and Joe Bryan, while Aden Flint was not fit enough for a place in the squad after hobbling out of the weekend victory at Shrewsbury.
Straight away a confident-looking City were on the front foot, as Wade Elliott spotted the run of Baldock, who nipped in front of last defender Mark Little and prodded the ball beyond Bobby Olejnik only for Little to make a last-ditch clearance before the ball could cross the line.
However, it would prove only a temporary reprieve for the hosts, who fell behind inside ten minutes.
Again Elliott was involved, this time clipping a deep diagonal ball towards Brendan Moloney, whose header back across goal was gleefully nodded in by Baldock from six yards.
Elliott and Baldock had been the obvious standouts in the early exchanges, and the same two would combine again to double the Robins’ lead just six minutes later.
Derrick Williams’ long ball was flicked on by Jay Emmanuel-Thomas to put Elliott in the clear. When Olejnik came to meet him, the veteran did well to scoop the ball over the keeper and then even better to watch it drop and calmly stroke a pass across the six-yard box for Baldock to tap home his second.
City were cruising, but an off-the-ball incident soon threw Posh a lifeline and left the visitors with 70 minutes to play with a man short.
It was the assistant referee in the City left-back position who spotted something break out between El-Abd and Peterborough’s top scorer Assombalonga, and duly relayed what he saw to prompt man in the middle Andy Woolmer to brandish a straight red card.
The whole episode remained something of a mystery to the vast majority inside London Road but certainly lifted the home crowd, whose players went up a gear with them.
Man in form Nicky Ajose found himself unmarked to shoot from 15 yards only for a deflection to take the ball wide of goal with Fielding beaten.
But, that chance aside, Peterborough struggled to take advantage of the extra man until Bostwick headed them back into the contest just a minute before the interval – by which time City had missed a glorious chance to lead 3-0.
More excellent work from the industrious Baldock saw the striker sneak around the back of the Posh defence again and this time set up Wagstaff, who connected cleanly with a first-time shot from 12 yards but sent his left-footed effort straight at Olejnik.
It threatened to prove a big turning point as Bostwick rose highest to convert Grant McCann’s corner with minimum fuss. Perhaps El-Abd had been the defender’s assigned marker.
There was still time for Emmanuel-Thomas, who was having a very quiet night, to try his luck from 35 yards with a fizzing free kick which Olejnik only uncomfortably kept at bay.
All footballing logic pointed to a second half chock-full of City defending, with the man advantage and momentum of the game’s third goal making for an uncomfortable Cotterill team talk.
The opening exchanges after the restart suggested no different, as Peterborough, who were back out ready to kick-off five minutes early, tore into their depleted visitors.
First City survived an almighty scramble which culminated in Assombalonga’s shot being diverted for a corner before Little, Bostwick and Josh McQuoid (twice) all worried Fielding from distance.
It was a constant blue wave of attacks but City were proving a tough nut to crack, as epitomised by Simon Gillett’s lunging block to deflect Tommy Rowe’s shot and Fielding’s handling in not allowing the ball to escape from his grasp.
The pressure was cranking up, but Fielding reacted brilliantly when Ajose rediverted McQuoid’s shot inside a crowded penalty area to tip it over the bar and secure three most unlikely points.