Gabriel Jesus’ early strike put the hosts in command at the Etihad Stadium, and Riyad Mahrez’s low finish ensured Pep Guardiola’s side held a two-goal league at the break.
An unfortunate Federico Fernández own goal extended City’s advantage before David Silva’s eyecatching free kick and Raheem Sterling's late strike finished the scoring, leaving United to taste defeat in the league for the first time since a 1-0 reverse at Crystal Palace almost five months ago.
A much-changed Magpies side started with intent but once Mahrez tested Dúbravka from distance, City took charge of the contest. Phil Foden combined with Silva down the left and his low delivery was met by Jesus, whose sidefooted finish was measured to perfection, dropping just inside the post.
A trademark long pass from goalkeeper Ederson then saw Mahrez warm the United stopper’s gloves again but barely 20 minutes in, the hosts made it two. The Magpies lost possession and couldn’t prevent De Bruyne’s burst into the box, and the Belgian’s cutback was diverted home by Mahrez.
One of United’s ventures forwards resulted in Fernández planting a header straight at Ederson after Matt Ritchie’s free kick picked him out at the far post and the chance heralded a better spell from the visitors, but ultimately they could easily have gone three behind before the break. Jonjo Shelvey was robbed of possession 25 yards out and some quick exchanges gave Foden a sight of goal, but with that bottom right-hand corner looking set to bulge once more, the youngster pulled his shot wide.
A few minutes after the restart, Foden squandered an even clearer opening. Another De Bruyne run into the box culminated in a high, hooked cross to the far post, where Foden somehow prodded the dropping ball wide of the target from just a couple of yards out.
But just before the hour, Guardiola’s men did find a third, albeit in the most fortuitous circumstances. It came following Jesus’ mazy dribble into the box which looked as though it would end with the Brazilian firing goalwards, but just before he did Matt Ritchie intervened. His challenge diverted the ball onto Fernández and the deflection left Dúbravka helpless as it flicked off the upright on its way in.
City’s fourth, though, was one of quality. With United having lined up a wall and De Bruyne and Silva both keen to take a free kick from just outside the area, the latter stepped up and curled home a fine goal, with United's Slovakian stopper again powerless to prevent it.
And in stoppage time, substitute Sterling to add extra gloss to the scoreline when Nabil Bentaleb surrendered the ball in the middle. City broke and Silva squared it for the England international, who rolled home a fifth to end a miserable evening and confirm Newcastle’s first Premier League defeat since February.
