Ferguson labelled last week's trip to Liverpool as his biggest game of the season and a 1-1 draw saw his Manchester United side surrender pole position to their city rivals.
Raring to go: Sir Alex Ferguson is ready for the challenge of Manchester City
Sunday's derby at Old Trafford gives the teams - both buoyed by midweek wins in the Champions League - a chance to lay down an early marker and Ferguson is looking forward to the clash.
Cool head: Wayne Rooney's two penalties dumped Romanians Galati
He said: 'I think the last couple of years they (City) have become more intense and there is more importance attached to them. On Sunday it's top of the league and second top, and it really builds up into a fantastic prospect for everyone and I'm looking forward to that.'
United needed two Wayne Rooney penalties to see off Otelul Galati in Romania while Sergio Aguero's injury-time goal earned City a 2-1 win over Villarreal - their first victory in their debut season in the competition.
Crunch time: Michael Carrick (centre) wants to finish the week with a derby win
Old Trafford midfiedler Michael Carrick admitted that, despite the results, things hadn't gone quite according to plan against Liverpool and Galati but is eyeing a big performance against their neighbours on Sunday.
He said: 'It's a massive game. Obviously it's been a tough week. The first two games have gone okay, so hopefully we can finish it off well.'
Late show: Sergio Aguero (left) fired Manchester City to victory over Villarreal
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