MANCHESTER:  For the past few years the Manchester derby has defined not only the balance of football power in the city but the balance of power within the Premier League. No longer. Not since Chelsea’s resurgence this season.

Still victory courtesy of a single goal from Sergio Aguero, was probably more important for City this time around than for United. Louis Van Gaal and the red half of Manchester know that they are in the middle of rebuilding job; City needed to halt a slump in form after a three-match slump which had included defeats in their previous two games plus a draw.

Of course the nightmare scenario for the champions would have been to lose to United in front of their own fans, a stage on which they had won 4-1 last term.

This time last season, David Moyes had upset United fans with his comment that City were a club which United aimed to emulate. No such defeatist talk from managerial successor Louis Van Gaal.

When asked on Friday if United could still be classed as a bigger club than their cross-town rivals, the Dutchman responded simply: “Of course.”

He explained: “Abroad we have more fans and more followers on social media. FC Bayern are also the biggest club in Germany. The same for Real Madrid and Barcelona. It will take a long time for Manchester City to reach that level.”

The challenge for United and Van Gaal was to prove it. In the derby, they had won five of the six most recent meetings. In two of the last three seasons, they had registered 7-1 aggregate victories against their local rivals. Not since a Robin van Persie inspired last-minute scramble in November 2012 had United won a league derby.

Old friends

Like their United’s manager, new Angel Di Maria and Marcos Rojo had both been scornful of City in the run-up to the game, setting aside their friendships with rival Argentinians Sergio Aguero and Zabaleta. Still, the threat Aguero posed could not be underrated.

Alfio Basile, former Argentina manager, had raised the stakes this week by nominating Aguero as the finest player in the world at the moment, ahead of both Cristiano Ronaldo and Leo Messi. ‘All’ he had to do now was take the challenge to United.

‘Kun’ did precisely that must after midway through the second half with his 10th league goal. The advantage was overdue with United having been reduced to 10 men in the first half by the expulsion of Chris Smalling and then seeing Marcos Rojo carried off on a stretcher with a shoulder injury after throwing himself at Martin Demichelis.

City also had several penalty appeals turned down by referee Michael Oliver on their way to a win which kept Chelsea just about in their sights, albeit six points further forward.

Van Gaal will have been disappointed not only with the unnecessary nature of Smalling’s red card but by the penetrative failure of his star-studded attack of Angel Di Maria, Robin Van Persie and captain Wayne Rooney, back after suspension.

City could have taken command early on. United keeper David De Gea made brave saves from Jesus Navas and Aguero, both players collecting an injury in the process.

Then Smalling let the heat of derby tension affect him. First he was yellow-carded for charging down a clearance attempt by City goalkeeper Joe Hart then he flew in at James Milner with a recklessness which brought inevitable dismissal.

City duly ended the deadlock in the 63rd minute with Aguero shooting home after a smooth crossfield move featuring Yaya Toure and Gael Clichy.