Iheanacho didn’t come in as manager Manuel Pellegrini chose to bring in Wilfried Bony for Argentine striker Sergio Aguero.
City captain Vincent Kompany headed in David Silva’s corner for the second and midfielder Fernandinho rounded off a superb team display with a thumping shot past Begovic, who was blameless for all three goals.
But Chelsea were unable to find a way back into the game as Ramires had a goal disallowed for offside and Eden Hazard was denied by Joe Hart in the second half.
The 34-year-old was replaced by Kurt Zouma with City leading 1-0 – the first time he has been taken off by Mourinho in the Premier League.
Pellegrini’s side finished second behind Premier League winners Chelsea in 2014-15, eight points off the pace.
The Frenchman, 24, made a £31.8million move from Porto to City in August last year, featuring 25 times in the league in his first season.
In the first half each team had chances at goal but the most fell to City and it paid off in the 32nd minute when Aguero scored their opening goal to make it 1-0 to City. While the Special One feels that that the 3-0 scoreline was “completely fake”, Pellegrini argued that the victory in front of their home crowd was “the least we deserved”.
“We were the best team by far in the second half”.
Mourinho said in May that Terry would have left Chelsea without him.
Kompany believes that it was the preparation for the game by the team along with the fact that the fixtures are less cluttered at the start of the season, that helped last year’s runners up send out a title warning. “Now they have that desire to win every game and the only way to do it is to play consistently for 90 minutes”, the Chilean told reporters after his side stormed to the top of the table.
Zouma is a different player to John Terry and Gary Cahill. I know they are going to play counter attack and long balls to Aguero.
“I am happy for people to say Arsenal, Liverpool, [Manchester] United and Chelsea are the favourites”.