Goals by Sergio Aguero, Vincent Kompany and Fernandinho were the least City deserved for a dominant display against a side who took 70 minutes to register a shot on target. Aguero had already been causing Terry and central defensive partner Cahill headaches and had three sights of goal in the opening 30 minutes before finally putting his side ahead.
The Argentine played a one-two with Yaya Toure in a crowded area, wriggled into space past a lumbering Cahill and fired the ball just inside Asmir Begovic's post. City manager Manuel Pellegrini said that a particularly sharp Aguero was unlucky not to have scored more in the first half.
"I am very satisfied because it is not easy to beat the champions - Chelsea were the best team, they won the title last season - and I think that the first 45 minutes that we played, we really deserved three goals, at least three goals," said the Chilean after the match.
"We played really well, without any disruption in defending, without conceding any chances for Chelsea to score, and we create at least four clear chances. It would have been more but Begovic had a great performance. We couldn't score more goals. In the second half, maybe we had some restrictions by the yellow cards, so the intensity was not the same. But, in our worst moments, Chelsea really didn't have chances, and then finally we score the two other goals that we deserved in the first half."
Hazard had Chelsea's one real chance in the 70th minute but fired a shot straight at Joe Hartbefore City's defenders cleared the loose ball with Costa lurking.
Kompany's glancing header gave City breathing space before Branislav Ivanovic gave the ball away and Fernandinho completed Chelsea's misery with a clinical finish past Begovic, who could have expected more protection on his first start in place of the suspended Thibaut Courtois.
For Pellegrini, these two goals were fully deserved by his team and reflected Manchester City's dominance for most of the match. However, he was quick to add there is a long way to go in the season, despite holding a five-point lead over their rivals after just two games played.
"In football nothing is indicative until the end of the season. Remember that last season Chelsea was eight points in front of our team, and at the end of December, the beginning of January, we were in the same position of the table. It is important not to drop points here, it is important not to drop against big teams, especially against the champions of last year, that continue to be the favourites of this year," said Pellegrini.
"Always the gap you have with the five big teams is important but we are just starting and just thinking of the next game and not for sending message or thinking what will happen in the month of May."