The Blues edged a heavyweight tussle at the Etihad Stadium on Monday to draw level on points with City.
A 1-0 win on the road means both clubs are now two points adrift of leaders Arsenal in the battle to land the top-flight crown.
Chelsea would appear to be very much in that hunt, but Jose Mourinho has claimed that his side are outsiders to prevail in a three-horse race.
Cech agrees, with the experienced shot-stopper refusing to read too much into one result with there still 14 games to come.
He told his personal website: "If we had lost, they would have been six points in front of us. This way it's level.
"In my opinion, City are still the biggest favourites to win the title.
"Arsenal are two points above them but for us nothing changes. We are carrying on and need to confirm this win with another in the home match versus Newcastle."
While reluctant to let emotions run wild after victory at the Etihad, Cech admits that Chelsea put in a hugely-impressive display at the home of a title rival.
He added: "It's a great result and extremely important to us.
"We played well from start to finish and had plenty of bad luck as we hit the woodwork three times.
"We could have won by a higher margin but worked hard until the final whistle was blown and deserved to get the win."