Sergio Aguero scored a hat-trick as Chelsea were humiliated at the Etihad Stadium.
The Blues, thrashed 4-0 at Bournemouth in their previous away game, were four down against the champions within 25 minutes.
Raheem Sterling put Manchester City ahead after just four minutes and Aguero doubled their lead with a stunning goal eight minutes later.
Aguero helped himself to another goal after an appalling error by Ross Barkley, before İlkay Gündoğan netted the fourth.
Aguero completed his hat-trick with a penalty 11 minutes into the second half after Sterling had been fouled by Cesar Azpilicueta.
And Sterling added the sixth with 10 minutes remaining to add insult to injury for Chelsea, whose defeat was the club’s heaviest since 1991.