Oh, Manchester, so much to answer for: coins thrown, blood spilled, fans goaded and pitch invasions. But do not pretend that you did not enjoy every last tackle made, goal scored and harsh word exchanged.
If it turns out a supporter is charged with racist abuse then that is something we can all condemn. The blood streaming down Rio Ferdinand's face at the end, hit by a coin from the crowd, was not English football's finest hour. Yet none of that could detract from the compelling tension of a game that was decided by Robin van Persie's moment of brilliance in injury time.
Blood, sweat and jeers. Fear and loathing. Tom Cruise in the VIP seats. Manchester's day of thunder. It is remarkable that this Manchester United side find themselves six points clear at the top of the Premier League. Yesterday came down to the finest of margins, a Van Persie free-kick, but there was so much more before then.
Mancini got it wrong by picking Mario Balotelli, who was eventually replaced by Carlos Tevez on 52 minutes, the man who should have started the game and City promptly responded with two goals that pulled them back into the match. By the end of it, with Tevez and the eternal substitute Edin Dzeko on the field, City might even have won the game.
Rooney picked City off with goals on 16 minutes, and then just before the half hour, At two goals up, United looked dominant. They might even have had more while City's best chances at the start of the game were a distant memory.
Yaya Touré scored City's first after Tevez had cut it back to City's barnstormer of a midfielder for his goal. In the closing stages it seemed like City could win it. Silva's shot hit David de Gea and then struck the bar. Then, with four minutes of regular time left, Zabaleta equalised with a low shot from a corner that clipped the substitute Phil Jones on its way in.
Then came Van Persie's winner, in off Nasri who did a poor job of trying to block it. A City supporter ran on to the pitch, making it as far as Ferdinand and then thinking better of it.
It was not as if these two sides had any shortage of aggravation between them before yesterday. They have a whole lot more now.