Roberto Mancini has warned his title contenders they would be foolish to underestimate Norwich tomorrow at Carrow Road.

The Italian continues to publicly concede the Premier League crown to cross-city rivals United, despite closing the gap at the top to five points in midweek. Sir Alex Ferguson is scheduled to bring his side to the Etihad later this month for what could still be an epic title decider – but the wily Mancini knows beating the Canaries will be a tough ask.

'The derby is easy,' he said. 'We can lose it but it is not a hard game. We don't have any problem with it. You know when you play against United or Chelsea, your concentration is 100%. The problem will be against Norwich. Against Norwich you might think it is an easy game. But it will be really tough. They are a good team and we have only had two days to recover. It is very difficult (to win the league), that doesn't mean we don't want to try or we don't have a small chance to win. But I hope we play like we did until three or four weeks ago, not how we played against Arsenal.'

Mancini launched a staunch defence of his reign on the eve of the club's trip to Norfolk with the Blues still on course for a best-ever Premier League finish after lifting last season's FA Cup and qualifying for their first-ever Champions League campaign.

'We should be proud of the job we have done until this moment,' he said. 'It is our best season since 1968, when Manchester City won the championship. We have a serious owner and serious chairman. They understand this. People who are very serious do not think if we lose two or three games they want to change everything. And if we had a bad season, what about the teams who are 10 or 15 points behind?'

Mancini acknowledges the huge outlay lavished on his squad from the club's mega-rich owner Sheikh Mansour raises expectations, but cautions City have also built for the longer term. 'When I arrived here the owners told me they wanted to go in the Champions League and fight for the title in two or three years,' he said. 'After one year we finished third with Chelsea and won the FA Cup. In the second we have fought for the title until now. All the time, people say we have spent money.

'But it is only like the other teams. In the last seven or eight years, they have spent �400-�500million as well. We didn't buy Cristiano Ronaldo, Lionel Messi or Andres Iniesta. If we bought Messi, we should win. We would have a player who scored two goals in every game. But we bought young players who need to improve together.'

Mancini's squad is again without the suspended enigma that is Mario Balotelli, who serves the second of a three game ban for violent conduct following his Arsenal sending off.

The Blues' boss has accepted his wayward striker's latest apology, but warned the time has come for actions rather than words if he is to remain part of Mancini's squad.

'We are happy but it doesn't change the situation,' he said. 'If he wants to stay he should change his mind. I spoke with Mario a lot of times about this. I don't think he can stay here for 10 years together with me. This is impossible.

'But if tomorrow, or in two or three years, he changes managers or squads, it is important he changes his behaviour. He has a lot of quality but he can lose it with his attitude.'