Manchester United manager David Moyes said rivals City are "at the sort of level we are aspiring to" after Manuel Pellegrini's men ran out 3-0 winners at Old Trafford.
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City head back across Manchester with all three points after seeing off their fiercest foes with remarkable ease -- United's second successive 3-0 home defeat in the Premier League after their loss to Liverpool.
And the performance left Moyes struggling to contain his admiration.
He is quoted by the Mirror as saying: "We have played a very good side, playing at the sort of level we are aspiring to. We need to come up a couple of levels ourselves because at the moment we are not there."
He added: "We didn't start the game well. They were very good but we grew into the game and up into the second goal we had a fighting chance. But we weren't good enough in the end."
The night could have been even worse after Marouane Fellaini was perhaps fortunate not to see red after appearing to throw an elbow at Pablo Zabaleta.
Moyes said: "My first feeling was that Fellaini's yellow card of a foul on Pablo Zabaleta wasn't even a free-kick, but I genuinely haven't seen it again and people have said to me that it was worse than that."