The Blues were far from their best on a chilly night in the north-east, but with Leicester and Tottenham both winning as well, this was a crucial three points in this most fascinating of title races.
And with the Foxes and Spurs next up, anything other than a win at the Stadium of Light would have been a severe blow to the Blues’ title aspirations.
Manuel Pellegrini, overseeing his 100th Premier League game, made five changes from the side that comprehensively swept Aston Villa aside at the weekend.
Kelechi Iheanacho retained his place while Joe Hart, Martin Demichelis, Yaya Toure, David Silva and Aguero all returned to the starting XI
...Sunderland 0 City 1...
With the Blues’ recent away form picking up over the past month and Sunderland embroiled in a relegation battle, City started this game as strong favourites.
Aguero went close with a long-range effort as the Blues started confidently and it was the in-form Argentine striker – inevitably – who put the visitors ahead with just 16 minutes played.
The ball worked its way out towards Jesus Navas who whipped a deflected low cross into the box that fell perfectly for Aguero who sidestepped his marker before poking the ball over Mannone and into the net.
There was concern immediately after due to Billy Jones’ crude attempt to stop the City man but fortunately there was no serious damage caused other than stud marks down Kun’s calf.
The Blues remained on top until the half-hour mark but it was Sunderland who finished the half stronger and on 34 minutes, Lamine Kone was guilty of glaring miss as he headed Jeremain Lens cross wide with the goal at his mercy.
City didn’t heed that warning and a minute before the break had Hart to thank for keeping out the improving Black Cats as Jermain Defoe worked an opportunity in the box and fired in a low drive that the England keeper somehow pushed out and Jones smacked the loose ball against the post.
The Blues had taken their foot off the gas somewhat and Sunderland were, at that stage, in the ascendency. Sensing an onslaught, Pellegrini replaced Iheanacho with Fernando in a bid to bolster the midfield.
It was a strange game in many ways with City unable to find a second goal and the hosts continuing to knock on the door throughout the second-half
...Sunderland 0 City 1...
Defoe, whose flailing arm caught Demichelis plum in the cheek in the opening period was fortunate again not to see red with a similar challenge on Nicolas Otamendi - both he and compatriot Demichelis vented their anger at the former Spurs man following the second offence.
The Black Cats’ new signings had clearly given their team impetus, and in the closing stages John O’Shea blazed over from close range and then a series of superb corners from new boy Khazri caused all kinds of problems for the Blues.
Hart was again called upon to make a fine save from Jones and the final moments were frantic and, at times desperate, as Sunderland peppered City’s goal from all angles.
Then, in the fifth minute of injury time, man-of-the-match Otamendi heroically headed off the line under severe pressure when it seemed the Blues’ resistance would finally buckle.
Then, to the relief of the travelling Blue Army, the final whistle.
Though it wasn’t pleasant to watch, City showed grit, determination and even though they were far from their best, banked three more precious points ahead of Saturday’s top of the table clash with the Foxes.
