Pep Guardiola’s side won seven from seven across all competitions, scoring 25 goals and conceding just once, leaving the Blues top of the Premier League table and Champions League Group F, and into the last-16 of the Carabao Cup.
Here, our writers look back over September and pick their favourite game.
Rob Pollard: Chelsea 0-1 City
In a month that saw City register 4-0, 5-0 and 6-0 wins, it may seem strange to choose a 1-0 win as the game of the month – but this victory at the home of the champions was special.
This was Pep Guardiola’s side laying down a marker, playing the kind of football that strikes fear into rivals; quick passing and movement, with intense pressing high up the field to quickly reclaim the ball whenever it was lost. It was perhaps the most one-sided top-four match the Premier League has produced in years.
Chelsea could hardly get on the ball, such was City’s dominance.
Kevin De Bruyne’s winner was superb – another from outside the box by the Belgian - and the home side had no reply. The truth is 1-0 flattered the Londoners.
John Edwards: City 2-0 Shakhtar
September was a period in which City hit goals with consummate ease and any of those free-scoring shows could easily lay claim to being the most enjoyable of the month.
But, the Blues were made to work a lot harder for their victory against Shakhtar and that made it all the sweeter.
Technically gifted and knocking the ball around nicely, City were almost playing a version of themselves for much of the game. It made for compelling viewing as the Ukrainians tested Pep Guardiola’s team in a manner in which many have failed to do so.
It provided a welcome reminder of this side’s defensive capabilities and, allied to Kevin De Bruyne’s fine strike and David Silva’s exquisite passing, there was plenty to enjoy and admire.
David Clayton: City 5-0 Liverpool
For somebody who has grown up watching Liverpool habitually thrash City at Maine Road, the 5-0 win over the Merseysiders was a long time coming.
It was a great game and, in fairness, very open and even for the first half-hour or so when things could have gone either way. As the half progressed and Aguero put City ahead, the axis started to swing the Blues’ way but Sadio Mane’s red card obviously helped matters.
What followed was a ruthless demonstration of how to exploit the one-man advantage with further goals Gabriel Jesus and two terrific late strikes from Leroy Sane adding the icing on the cake.
It was our biggest win over Liverpool for several decades and, for me at least, was payback for all those days I walked out of the ground as a kid feeling like the world had ended!