Manchester United: Incredible how far the mighty have fallen
Edin Dzeko is no Denis Law, yet his goals last night were a symbolic reminder of the last time City enjoyed this kind of imperious dominance over their neighbours.
Law's back heel on this turf sent United spiralling out of English football's top flight and City into paroxysms of delight.
Forty years on, the dynamics of the Premier League make it all but impossible for United to experience relegation again. The fundamentals have changed at City, too. No longer content to run off into the Manchester night with bragging rights alone, City haven stolen United's power.
They are the club chasing the big prizes, while United adjust to reduced circumstances, if not in the second tier of the game, certainly a level beneath City in the top flight. City manager Manuel Pellegrini expected to win this contest and he did, without breaking step.
If it is any consolation for David Moyes, defeat No 10 of a torrid season was by no means the worst. This was no cause for shame. His team showed some fight and he demonstrated his readiness to adapt when it was so obviously going wrong.
The removal of the over-matched Tom Cleverley at half time was a kindness to a player who has clearly found his level. And this is not it. Cleverley epitomised the difference between the teams, one-paced, bereft of confidence and risk averse.
Manchester lightweight Anthony Crolla was introduced to the crowd half an hour before kick off. Crolla, a lifelong United fan, is involved in derby of his own next month taking on City supporting Manc John Murray in a world title eliminator. Looking at the team sheet, the thought occurred he might be a better option than Cleverley if his selection was predicated on shackling the marvellous David Silva.
One punch might have been enough. Cleverley never got close to landing one, mind you he was not alone in that.
In one sense Cleverley has done his manager a great service this season, absorbing the stick that might have come the way of Moyes. The reluctance of the majority to condemn Moyes for the enduring disappointment of his short reign diverted the pent up criticism Cleverley's way. His reward was to be given a start in a match of huge importance.
United were a goal down before Cleverley had touched the ball, but that fact applied to most of his team-mates. On the plus side they kept out Silva's first attempt.
City did to United what Barcelona did to them, which begged the question why they were unable to summon the same arrogance when it mattered in Europe. Failure in the Champions League points to a lingering esteem issue when confronted by the major powers in Europe that still needs to be addressed.
Observing Silva co-ordinating the best of everything in that fearsome opening salvo, a mesmeric presence behind Dzeko, it's hard to imagine City will be forever caught in the headlights of Munich, Madrid and Barcelona.
This is the role earmarked at United for Juan Mata, who is just as inventive but the locomotion around him had nothing like the fluid rhythm that kept Silva in business, but then again there is no Yaya Tour or Samir Nasri in this United team.
There was a point 12 minutes from the end of the first half when Fernandinho made a rare error misjudging the flight of the ball and heading into space down the right.
Rooney looked for the raiding red shirt that would have been there not too long ago. Instead there was Cleverley, labouring in no man's land, neither here nor there.
Again this was not wholly his fault, but a consequence of how the team was set up and the job he was asked to do. It is all right panning Olympiakos and running through West Ham but this is the ultimate test of a manager's credentials, to scheme your way past the best.
With five minutes of the half remaining after United had enjoyed their best spell of the evening , Moyes had the baton out in the technical area waving Cleverley into position to take the ball off his defence.
The player duly responded, turned and passed directly to the opposition. His team was under pressure needlessly and Moyes twitched sideways as if stabbed with a cattle prod.
This was the moment his night ended. It might be the end of his United career as Moyes ponders a clear-out at season's end, assuming he is not part of it.