City must now beat Bayern Munich in their final Group A game next month and hope for a favour from winless Villarreal to progress to the knockout stage after losing 2-1 at the San Paolo Stadium. Highly-rated Uruguay forward Edinson Cavani struck both goals for the hosts either side of a Mario Balotelli equaliser on another tough European night for the Barclays Premier League leaders.
Mancini said: "I am disappointed about the result and I am sorry for the lads. I think we lost undeservedly. We played a very good match and we conceded two goals we shouldn't have done. There is nothing to explain, we are a strong team and we always play well, we always play to win. But occasionally you can lose matches, especially in the Champions League."
He added: "I am not too disappointed. We have still got another match to play and if we don't qualify we will play Europa League. Our target was to go into the second stage and at this moment we are depending on other teams. But in football anything can happen. If Villarreal play a serious match they can get a result. It is important we play our game against Bayern Munich."
Mancini admitted, however that the chances of progress were probably a "70% to Napoli and 30% to us".
As well as scoring, Balotelli had a number of other chances and was also sick on the field, but Mancini rubbished suggestions the maverick Italian forward might have been ill after being spotted in a pizzeria in Naples with his girlfriend on the eve of the match.
"He was sick but he didn't have many problems," Mancini said: "He has a small fever, it was nothing serious. He had my permission to see his girlfriend for half an hour - it was only to say hello to his girlfriend in a pizzeria. He did not have a pizza."
David Silva and Aleksandar Kolarov had good opportunities for City in an eventful game but Marek Hamsik also hit the post for Napoli, who dominated for long spells.
Mancini said: "We knew how Napoli play, they wait behind and counter-attack. We conceded too much space to them, but I am happy with ball possession and the chances we created. I am disappointed about the result but not about the performance.
"I think both teams are excellent teams, they are improving at the moment. We need to accept the result. We made mistakes. When you are against players like Hamsik, (Ezequiel) Lavezzi and Cavani they can put you under pressure."
Source: PA
Source: PA