Mancini: Cup triumph helped City
It has been an amazing season for the Blues so far, capped by their staggering 6-1 away win over Manchester United at Old Trafford in October.
They reached the end of the festive programme three points clear of United and well placed to end the season as champions for the first time since 1968.
However, as Sir Alex Ferguson brings his players to the blue half of a divided city for an eagerly-anticipated FA Cup third-round tie, Mancini acknowledges what a boost lifting the trophy last season gave everyone at the Etihad Stadium.
United were accounted for in a Wembley semi-final before City returned to defeat Stoke City and end a trophy drought that extended to 35 years. "It was really important for the club," said Mancini.
"When you build a new team you have to start to win very quickly. If you get one cup, in that moment you can understand if you work hard and win the FA Cup, you can win the championship."
"We won it last year and want to go in the final again if it is possible. It is a difficult game. It is a derby. It is harder because they are angry after two defeats and they are usually very strong after a defeat. But it is not important for the Premier League, other than maybe physiologically."