The two Manchester clubs went goal crazy yesterday, sending a statement to the rest of the Premier League that this could be a two-horse title race.
And Manchester United answered that call, beating Arsenal, Tottenham's North London neighbours, 8-2 at Old Trafford to go top of the table on goal difference from City.
The humiliating result also puts more pressure on Arsene Wenger, the beleaguered Arsenal manager who has seen two of this best players - Cesc Fabregas and Samir Nasri - leave in the summer. His team are now fourth from bottom and without a league win this season.
In a frightening example of attacking play, the rest of the league was left to marvel at the attacking prowess of both teams.
Nasri, who joined City on Wednesday, was one of the stars against Spurs, setting up three goals, while Edin Dzeko scored four. And the Bosnian striker believes City have yet to peak.
"Today was something special for me, to score four goals in the Premier League is fantastic," Dzeko said on ESPN. "I think we're getting better and better. I hope we can improve in the next game and try to win every game."
Nasri said: "This is a tough place to win. I had a good game but the most important thing is we won 5-1 and sent out a signal to other clubs. This is just the start of the season, it's important to keep our confidence, but I'm convinced we have a great team here and can win things."
Wayne Rooney was also in the goals, helping himself to a hat-trick, as United romped past Arsenal to register one of the biggest ever Premier League victories.
"The performance was incredible and we deserved the result," Rooney, told Sky Sports."Whether or not Arsenal have a full-strength squad every time we play them we have a go and try score. They had some players out but that should take nothing away from us."
Rooney's goals also continued a trend against the Gunners. "A lot of my milestone goals have come against Arsenal," he said. "My first goal when I was at Everton was against them and my first United goal in the Premier League came against them too."
Sir Alex Ferguson, the United manager, was surprised by the ease of his side's success despite Arsenal missing so many first-team regulars. "When you play Arsenal you expect a difficult game," he said. "If you look at Arsenal the team is weakened - but we still did the job."
With Wenger likely to come in for more criticism, Ferguson again leapt to the Frenchman's defence.
"I think it is unfair to criticise him," he said. "The job he's done for Arsenal and the philosophy he has - he has given Arsenal some very entertaining players."
Wenger acknowledged he had been left embarrassed by the size of the defeat, but with the pressure mounting on him denied he would quit his post.
"You feel humiliated when you concede eight goals," he said. "It was a terrible day for us, it was a combination of an understrength team and weakness. We collapsed physically in the second half."
He added: "It is better not to talk too much about this because it hurts."
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