Pep Guardiola opted for two changes from last time out, with Mahrez and captain Fernandinho replacing Rodri and Silva. Ederson and Scott Carson remained out with Covid-19, so Steffen continued in goal, while 18-year-old goalkeeper Trafford filled in on the bench.
Ole Gunnar Solskjaer made two changes to his starting eleven that defeated Villa. De Gea was rotated out for cup goalkeeper Henderson and Lindelof came in for Bailly to partner Maguire at the back.
The hosts dropped off and invited De Bruyne onto themin the 13th minute. The Belgian obliged and steered a right-footed effort towards the top left corner from 20 yards out. Unfortunately for the Citizens, his effort beat Henderson but cannoned into the left-hand post and back away from danger.
It had been a frantic opening to the game. Next, Scott McTominay shaped to shoot but instead fed Bruno Fernandes, who from 20 yards out aimed to curl one into the far corner. Steffen did well to move quickly, diving acrobatically to his left and tipping it over the bar to concede the first corner of the game.
Shortly after the interval, the Citizens won a penalty. Sterling beat McTominay not once but twice and on the second occasion the Scot fouled City's forward to give away a free-kick in a dangerous area on the left.
Phil Foden took the wide set-piece, crossing towards the near post. The youngster's cross evaded Mahrez at the near post but found Stones at the back post, where the centre-back finished past Henderson into the bottom right corner with his thigh.
That opener had given City some real impetus, this time Cancelo progressds towards the edge of the area before smashing a right-footed effort just over the bar. Henderson was left motionless after the Portuguese wing-back's effort but fortunately for the hosts it travelled over the target.
In the 57th minute, Ilkay Gundogan had options either side of him but opted for Foden, who reached the byline on the left before chipping a cross back towards the penalty spot. Sterling was the first to the cross, heading back towards the near post, where Henderson tipped it around the post for a corner to the visitors.
Five minutes later, United were sloppy in midfield, allowing City to intercept and counter-attack through Mahrez. The Algerian then went on his own, reaching the edge of the box before unleashing a left-footed effort towards Henderson's right but the English goalkeeper produced another great save to tip it over the bar.
In the 72nd minute, Pogba retrieved Rashford's wayward cross before finding the feet of Fernandes, who took his chance quickly but could only curl his right-footed effort just wide to the right of Steffen's goal from inside the area.
The Citiens got their two-goal cushion in the 83r minute. United dealt with the initial corner, heading out to the edge of the area. Fernandinho then greeted Wan-Bissaka's headed clearance by volleying it with his right foot into the bottom left corner. Henderson, perhaps unsighted, did not even move as the Brazilian's effort whistled past him to seal the victory for Guardiola's m