Defeat left United 12 points behind City just 12 games into the league season, with beaten manager Jose Mourinho accepting there was now a "gap" between the Manchester clubs.
Despite the tight turnaround after the World Cup, Manchester City's attacking ruthlessness has not been blunted by fatigue or the English heatwave. Winning the Community Shield demonstrated that beyond any doubt on Sunday. Take a look at the best moments from the match.
Manchester City were confirmed as English Premier League champions as rock-bottom West Brom stunned Manchester United with a 1-0 win at Old Trafford.
Mohammed Salah's strike helped Liverpool defeat Manchester City 2-1 in the Champions League quarterfinal second leg match to seal a 5-1 aggregate win over the EPL toppers.
Liverpool swept Manchester City aside with a three-goal blitz in 19 first-half minutes to take a commanding 3-0 first leg lead in their Champions League quarters.
IN PICTURES | Arsenal lose tough second-leg game against Ostersunds, scrape through to Europa League last 16
Two quickfire first-half goals gave Swedish minnows Ostersunds hope, but Sead Kolasinac's goal just after the interval saw Arsenal hang on for a 4-2 win on aggregate.
IN PICTURES | Manchester City suffer shock 1-0 defeat in intense game against Wigan Athletic, gets knocked out of FA Cup
Manchester City's quest to win the FA Cup an unprecedented fourth time came to a shocking end when the Pep Guardiola-led side fell to a 1-0 defeat against Wigan Athletic in the fifth round.
Sergio Aguero scored a quickfire brace in the second half as Manchester City maintained their interest in four trophies by beating Burnley 4-1 in the FA Cup third round match.
Raheem Sterling scored the quickest goal of the Premier League season at 38 seconds to set Manchester City on its way to a 3-1 win over Watford.
Raheem Sterling came on to score an 82nd-minute equaliser for 10-man Manchester City as they played out a 1-1 draw in their opener.