Manchester City 4
Manchester United 1
It is tempting to say the balance of power in Manchester has swung from red to blue. In reality it was catapulted Manchester City's way in an astonishing 90 minutes at the Etihad Stadium.
Manchester United were not just defeated, they were destroyed, embarrassed on an ignominious day for them.
If losing to Liverpool at Anfield was bad enough for David Moyes, this was disastrous. It was not merely the result, but the manner of the thrashing. United were appalling, over-run and overcome, overpowered as their elderly defence looked over the hill. City were rampaging and rampant.
Manuel Pellegrini replaced a manager, Roberto Mancini, whose popularity owed much to a 6-1 derby win. Now the Chilean has a victory to rival that.
His team were terrific. Joe Hart did not need to make a save until an hour had elapsed, and then it was to spare team-mate Matija Nastasic an own goal.
Yaya Toure has been City's derby trump card time and again and while Marouane Fellaini's arrival was supposed to give United a similar physical force in midfield, the Ivorian and Fernandinho ran the game. Sergio Aguero was electric and irrepressible in attack. He scored twice. His sidekick, Alvaro Negredo, set up two goals.
Perhaps they had momentum from the minute team sheets were submitted, without any sight of Robin van Persie's name. A groin strain sidelined the Dutchman, United's match-winner at the Etihad Stadium nine months ago. After a gashed forehead deprived United of Wayne Rooney's services at Anfield, it was another bitter blow for Moyes. Once again, however, United failed to compensate.
City set about United from the start, unsettling them by playing at pace. Their lead was deserved and came in style, Aguero hooking in Aleksandar Kolarov's cross with a left-foot volley.
On the stroke of half-time, they were two ahead. Negredo rose above Chris Smalling to meet Samir Nasri's corner; Toure stuck out a telescopic leg to turn the ball over the line. Then Negredo supplied a second assist, fooling Nemanja Vidic with his turn and finding the unmarked Aguero to sweep home his second.
Finally, Jesus Navas chipped a cross to the far post where Nasri volleyed in. It was a sweet moment for the Frenchman, blamed by Mancini for deflecting in van Persie's winner at the Etihad Stadium last year.
Four goals to the good after 50 minutes, City could cruise for the last 40, even if their efforts could have produced more. Instead, Rooney reduced the deficit with a record 11th derby strike. It was a historic moment but it mattered little. United had already been demolished.
City, once again, are the kings of Manchester.
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