A moment of indiscipline in the 3rd minute saw Wade Elliott sent off for violent conduct leaving City to play for most of the match with 10 players and although Swindon took a further 75 minutes to break down the City rearguard, Michael Smith’s thunderbolt goal was well worth waiting for.
The win moves Swindon into 2nd place with 32 points from 17 matches played in League One and City were left to reflect on losing their unbeaten League record.
Mark Cooper made three changes in his starting line-up from the previous match with Raphael Rossi-Branco, Ben Gladwin and Michael Smith starting in place of Yaser Kasim, Massimo Luongo and Andy Williams.
Bristol City kicked off playing towards the Town End in a raucous atmosphere backed by 2971 fans on the Stratton Bank and corner of the Arkells stand.
There was early drama when Wade Elliot appeared to floor Jack Stephens with two pushes to the face in the 3rd minute and the referee Darren Drysdale sent the City player off after consulting his nearby assistant.
Bristol City were smarting and lost their discipline further with two bad fouls in quick succession and Scott Wagstaff was shown a yellow card for the second foul.
Sadly there were two separate smoke bombs thrown from the City End which caused a brief delay in the match but order was soon restored.
City’s first attack in the 10th minute led to two corners in quick succession which Town cleared and launched an attack downfield.
Ben Gladwin started a decent attack in the 15th minute after picking up the ball in midfield and spraying the ball out to the right wing for Byrne to charge down the wing but his cross went behind for a goal kick.
Jon Obika also pressed strongly down the right and tricked his way into the area but his pass back to Gladwin went behind the Town midfielder and the chance was lost.
Town continued to push for the opening goal with Gladwin firing in a shot from 25 yards but his effort struck a defender the ball was eventually cleared after pinging about the penalty area in the 24th minute.
City earned a corner in the 27th minute when the ball was deflected behind by a defender but Town cleared thanks to a diving header by Rossi-Branco.
Further indiscipline by City saw Aaron Wilbraham cautioned for an unnecessary late challenge from behind on Nathan Thompson with the ball on its way out of play in the 30th minute.
A quick counterattack in the 34th minute saw Town switch the ball from right to left before Byrne fired wide of the goal much to the delight of the fans behind the goal.
Swindon conceded a free kick 40 yards from goal which was taken by Freeman but the Town defence stood firm and cleared the ball.
Town earned a corner when Byrne’s cross was deflected behind but the City defence cleared easily downfield in the 38th minute but Town pushed forward and went close following a free kick when Gladwin’s cross to the backpost only just evaded Rossi-Branco.
Michael Smith was shown a yellow card for a late challenge shoulder to shoulder with City keeper Frank Fielding in the 44th minute with Aden Flint getting involved unnecessarily.
Only two minutes of added time were played despite a number of interruptions with City slowing the game down and the whistle was blown to end the first half of this feisty West Country derby.
Town kicked off the second half but it was the visitors who went closest to opening the scoring when Bryan’s fierce shot went only just wide of the upright.
Town had a corner in the 51st minute but were unable to get a shot on goal before the ball was cleared downfield. However Jordan Turnbull tried his luck with a fierce shot from 25 yards in the 53rd minute but the keeper caught the effort cleanly.
Michael Smith went close for Town with a shot from 12 yards in the 54th minute but his effort was deflected out for a corner which was easily dealt with by the City keeper.
Greg Cunningham replaced Agard for City in the 58th minute just after Louis Thompson had been cautioned for a late challenge on Bryan near the corner flag in front of the Arkells Stand.
Town were enjoying plenty of possession with their numerical superiority without being able to find the final ball in front of goal but a spirited run by Toffolo almost opened the door but his cross was deflected behind by Flint.
Andy Williams replaced Jon Obika in the 66th minute and he left the field to good applause.
Some good defending by Korey Smith from a cross by Gladwin led to a corner but Town were unable to threaten from the cross.
Nathan Byrne rattled the crossbar with a fierce deflected shot in the 72nd minute as Town cranked up the pressure on 10 man City and two minutes later, Gladwin was denied by Fielding who dived to push his shot away for a corner. Todd Kane replaced Wagstaff during the break in play and when the corner was taken short to Byrne, his lobbed cross to the backpost was headed away by the City defence.
Town took a well deserved lead in the 78th minute when Michael Smith got possession of the ball near the penalty spot and after tricking his way past two defenders, fired powerfully to the right of Fielding in the City goal to send the Town fans into delirium! The goal was Smith’s 12th of the season and really ignited the atmosphere around the County Ground
At last Bristol City were forced to push forward after packing the defence for much of the match and trying to catch Town on the counterattack. Former Town target Marlon Pack replaced Bryan in the 86th minute as City manager Steve Cotterill looked desperately to try retain their unbeaten record.
Town earned a corner in the 87th minute but the resulting cross was easily caught by Fielding who launched an attack downfield which led to a shot high and wide by Agard.
City were looking more and more desperate as the match entered the 4 minutes of added time but their cause was not helped by Aden Flint’s foul on Williams near the corner flag which lost their momentum.
The final whistle was greeted with a tremendous roar as Town sealed a famous victory over Bristol City who were unbeaten in 16 league matches before today.