Goals from Ilkay Gundogan, Phil Foden and Kevin De Bruyne meant there was no way back for the hosts who were outplayed for the majority of the game before pulling a goal back with almost the last kick of the game.
Chelsea started brightly without ever really testing Premier League debutant Zack Steffen.
The hosts’ nimble front three of Timo Werner, Christian Pulisic and Hakim Ziyech were playing together as a unit for the first time, but they struggled to breach what has been a rock solid City backline this season.
Then Raheem Sterling saw his deflected shot saved by the keeper a few moments later.
But it was a brief respite for Chelsea, with City taking the lead on 18 minutes with a beautifully crafted team goal.
Gundogan found Oleks Zinchenko on the left and his low ball to Foden was nudged on by the youngster to Gundogan who span off his marker before drilling a low shot into the bottom right-hand corner from 15 yards out.
Two minutes and 35 seconds later – to be precise – City doubled the lead with a goal that was even more aesthetically pleasing than the first.
Zinchenko was again involved, finding De Bruyne who tried to thread Foden through – the ball came back to the Belgian who moved into the box before sending a pass through the legs of Azpilicueta and Foden’s delightful flick at the near post gave Mendy no chance.
It was mesmeric football and whether it was playing a side who weren’t parking the bus with ten men behind the ball or the clever tactic of playing Sterling and Foden on opposite flanks at various stages, but it was though some sort of psychological weight had been collectively lifted.
Chelsea’s probing continually met a wall of sky blue steel and on 34 minutes, a De Bruyne defensive header sent Sterling clear and after sizing up his options, the England forward curled a shot against the inside of the post and – of course – De Bruyne was the man to collect and drill home the rebound.
City started the second-half in the same manner the first ended, causing the hosts numerous headaches.
Chelsea improved from their first-half showing, but were no match for City in this mood.
Only a late counter-attack by Chelsea breached the City defence, with Callum Hudson-Odoi scoring in added time.