Chelsea 2 - 1 Man City
Frank Lampard came off the bench to score from the spot as Chelsea dealt 10-man Manchester City their first Premier League defeat of the season.
Mario Balotelli gave City an early lead when he gathered Sergio Aguero's cute pass before rounding Petr Cech.
Chelsea hit back when Daniel Sturridge crossed for Raul Meireles to volley in. And when Gael Clichy was sent off for a second booking before the hour, Lampard scored from 12 yards after Sturridge's shot was handled by Joleon Lescott.
The result was a complete turnaround from the first half where the visitors dominated, but having failed to extend their lead, Roberto Mancini's team were made to pay.
Defeat ends City's record run of 14 league games unbeaten, while victory for Chelsea adds another feather to manager Andre Villas-Boas's cap, who has overseen three crucial victories in the space of nine days.
Chelsea also move into third place in the Premier League, seven points behind leaders Manchester City.