Manchester City boss Roberto Mancini was still not totally satisfied after the 5-1 victory over the Canaries – because his side did not keep a clean sheet.

Steve Morison's goal, nine minutes from time, took a little of the gloss off another big win for the Premier League leaders.

'You know if you don't close the game it can be difficult. Usually when we are 3-0 we relax ourselves and we usually concede a stupid goal,' said Mancini in a radio interview after the game.

'We can't keep our concentration and I am very frustrated for this because I am sure if we were 1-0 we wouldn't concede a goal.

'I don't like to concede this goal. We need to keep our concentration for 95 minutes.'

Tactical coach David Platt, who attended the post-match Press conference for the written media, said Norwich had made it difficult in the opening half an hour until Sergio Aguero's opening goal.

'I think full credit to them. They got people behind the ball. They didn't want to open up too early,' he said.

'It was always going to take a little bit of brilliance in a tight area to open the game up. We know we've got that kind of player out there.

'You can get frustrated when you're sitting on the bench, thinking maybe we have got to do this or that, but I think it was just a matter of keep moving the ball, keep shifting around and then eventually it was going to open up, by a little bit of brilliance by somebody.'

Platt said there should not be an assumption that the leaders would score a hatful of goals every week.

'You hear things leading into the game, you're playing against a newly-promoted side – one that has done quite well this season and got into a mid-table position,' he said.

'People automatically assume now we are going to go out and score five, six, seven or eight goals when we come up against these teams.

'To be honest, we'd take one as long as there was no reply from it because that would get you three points all the same.'

Platt praised French international Samir Nasri, scorer of the second goal, from a free-kick, for his performance.

'Today he looked bright, very bright,' he said.

'His goal was a great ball in. The goalkeeper's probably going to be a little bit disappointed, but we've got runners across so sometimes that can happen.'