The Citizens struck early, finding the net through Sergio Aguero when he fired home from close range in the 16th minute.
The Argentine striker missed an early portion of the season through injury, but demonstrated his value once again with a fine effort to fire Manuel Pellegrini’s side into the lead.
The visitors rarely looked like losing control of the match after taking it, and even though Kelechi Iheanacho disappointed in tandem alongside Aguero, in Yaya Toure, they possessed the game’s outstanding individual.
Joe Hart also shone, tipping an effort from the home side round the bar, as Sunderland, buoyed by the presence of various new signings, rallied during the second half.
The win takes City up to second in the table, although they remain three points behind leaders Leicester City, who saw off Liverpool.
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Here are the Manchester City Player Ratings vs. Sunderland
Joe Hart 7/10
Bacary Sagna 7/10
Nicolas Otamendi 6.5/10
Martin Demichelis 7/10
Gael Clichy 7/10
Jesus Navas 7/10
Yaya Toure: 8.5/10
David Silva: 7.5/10
Kelechi Iheanacho: 6/10
Sergio Aguero: 7.5/10
Raheem Sterling: 5/10
Aleksandar Kolarov: 5/10