Aston Villa attempted to pull off a comeback in the second half but Man City did enough to pick up all three points.
Ruben Dias and Bernardo Silva got the goals for City as they battled for the victory.
Ollie Watkins got a goal back for Villa after the break as they made it tough for the visitors.
Jack Grealish was a late substitute on his first return to Villa Park since his £100million summer move to the Etihad to earn a mixed reception.
Chelsea’s 2-1 win at Watford made victory imperative for Man City and they sit a point behind the leaders in second.
Pep Guardiola, without injured Kevin De Bruyne and Ferran Torres and the banned Aymeric Laporte, had labelled his selection issues an “emergency” but he was still able to call on Phil Foden, Grealish and Cole Palmer to man the bench.
That other substitutes Luke Mbete, Romeo Lavia, Josh Wilson-Esbrand and James McAtee had just five senior appearances between them mattered little thanks to a merciless first-half which did the damage.
The visitors dominated from the start, playing exclusively in Villa’s half, and Emi Martinez needed to be alert to beat Joao Cancelo’s near-post drive behind inside the first 60 seconds.
He turned Rodrigo’s shot over three minutes later and City executed their high-level possession game perfectly – until they needed Dias to bail them out after 10 minutes.
John McGinn sent Watkins scampering down the left the ball was eventually smuggled to Leon Bailey but Dias’ last-ditch block denied him.
It was the only scare of the half and Gabriel Jesus then had a genuine penalty shout rejected by Mike Dean.
Villa, having held firm as City attempted to pass them into submission, carved out a foothold but continued to pick the wrong option going forward with Bailey, Matty Cash and Emi Buendia all guilty.
They then paid the price and found themselves behind after 27 minutes.
Raheem Sterling had been a menace and, this time, made it count when he found space on the left and his deep cutback found Dias arriving on the edge of the area to sweep a first-time shot into the bottom corner.
It gave City the breathing space they needed to exploit Villa and, two minutes before the break, they took the hosts apart to double their lead.
A sensational, ruthless, move started when Riyad Mahrez and Cancelo delicately played their way out of a tight space inside their own area for Fernandinho to release Jesus.
His early cross picked out Bernardo and the forward put the gloss on the stunning counter with a brilliant first-time volley which flew past Martinez from 18 yards.
Despite his allegiances to the hosts the quality would have surely earned royal approval from the watching Prince William but the future king was celebrating two minutes after the restart.
Steven Gerrard got the response as Villa pulled a goal back when Watkins fired Douglas Luiz’s corner in off the post.
It gave them belief and Nathan Ake poked Watkins’ knockdown behind, ahead of the lurking Ezri Konsa and surviving a brief VAR check for a penalty.
Unlike the majority of the first half City had to deal with some serious pressure as Villa refused to go quietly.
Jesus skied Bernardo’s cross over when he should have done better with 19 minutes left before Ederson earned City the points three minutes later.
Buendia’s skill and strength fashioned a glorious opening for Carney Chukwuemeka but, with just Ederson to beat, the 18-year-old shot too close to the goalkeeper who turned it over.