The defending champions claimed the three points in front of their home fans at The Etihad to highlight their Premier League title credentials heading into the final international break of 2018.
David Silva put the hosts ahead in the 12th minute, and Sergio Aguero made it 2-0 with a close-range finish into the roof of the net shortly after half-time.
Anthony Martial pulled a goal back from the penalty spot in the 58th minute after substitute Romelu Lukaku was brought down by Ederson in the box.
However, Ilkay Gundogan made the points secure for Pep Guardiola’s men when he controlled a pass in the box and fired past David De Gea in the 86th minute shortly after coming on.
The win left Manchester United two points clear of Liverpool FC at the top of the Premier League table and 12 points behind Jose Mourinho’s United, who are down in eighth place.
And England legend Lineker feels that the Red Devils clearly have some work to do if they want to catch their local rivals.
Lineker posted on Twitter shortly after the final whistle: “12 games played and @ManCity are 12 points ahead of @ManUtd. Huge gulf in class between the 2 sides at present.”
Earlier in the game, Lineker had written on the social network: “Superb football from @ManCity. They really are one hell of a side.”
Ex-midfielder Robbie Savage warned that Manchester United have some serious problems to address.
“To come here and have one attempt on target, which is a penalty… is that good enough for Manchester United?” Savage told BBC Sport.
“When you have spent that amount of money on attacking players? I feel Jose Mourinho always is one or two performances from people wondering ‘Will he still be here?'”
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