The Blues head to Old Trafford next Wednesday for the second leg of their Carling Cup semi-final knowing a draw will be enough to secure their first trip to Wembley in 29 years. Even a repeat of the seven-goal epic in September would do it, although the nerves of both sides would be shredded in the unlikely event of that occurrence.
"It was important to win my first derby - but I want to win my second as well," said Mancini.
"I wasn't nervous. But Manchester United are a big team and I know it is going to be difficult."
Mancini's immediate focus is City's FA Cup tie at Scunthorpe, when Stephen Ireland is likely to be among a large number of changes.
Patrick Vieira could also come into contention if he can shrug off a calf problem that has plagued the Frenchman since his arrival from Inter Milan.
Mancini is saying all the right things ahead of the trip to Glanford Park, insisting: "We want to win that cup tie as well, because the FA Cup is important too."
However, given the choice, the unanimous decision among the City faithful would be that defeat on Sunday can easily be compensated for by outright victory next week.
If there is a fear for City it is that they are stepping into the unknown. In reporting nerves among his troops in the opening stages, Mancini was raising doubts over their ability to handle the pressure at Old Trafford should the tie still be in the balance in the latter stages, but midfielder Vincent Kompany is in bullish mood.
He said: "If you are not going to be confident after a result like this, when are you going to be? It is the perfect situation and I believe we can score again. That is the big focus for us."