Pep Guardiola's men could not believe their luck when Gary Cahill acrobatically opened the scoring for them before half-time.
However, they were powerless to resist the Blues's fightback in the second half as Diego Costa, Willian and Eden Hazard led an impressive comeback.
2009 - This is the 1st time that Man City have lost a home league game that they were leading in since April 2009 v Fulham (1-3). Turnaround— OptaJoe (@OptaJoe) December 3, 2016
It is their first such loss at home since April 2009 when they surrendered a lead against Fulham to lose by the same 3-1 scoreline.