City were handed a lifeline in the title race after Manchester United suffered a shock 1-0 defeat by Wigan Athletic at the DW Stadium, cutting the Red Devils’ lead to five points at the top of the table.
Mancini’s side had produced a virtuoso performance, with Sergio Aguero scoring either side of half-time before Carlos Tévez netted his first goal since returning to the Eastlands outfit and David Silva adding a fourth.
“United are a fantastic team and I don’t think they can lose five points,” said Mancini.
“For us it is important that we finish this good season for us well. This is the best season since 1968 and this is important.
“I fight always, every day, and also my team but now I think it is too late.
“I think they have fantastic spirit, United. We don’t have the same spirit and for this reason I think this is very difficult.”
He added: “I thought they played tomorrow – only when the game finished I knew they had played tonight.”
Mancini heaped praise on City for their response after failing to win their previous three games, expressing his pleasure to see Tévez back on the score-sheet.
“I am pleased with all the players because it was important to come back and play like one month ago and to score four goals,” Mancini said.
“I am happy for Carlos because he scored a goal. He is not ready to play 90 minutes, it is difficult.
“If Carlos continues to play he can improve his performance.”
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