Mancini admits the drinking culture in England is very different to what it is in Italy.
“For a young player it is important to always behave well,” he explained. “I can understand sometimes things can happen on holiday but it is important for them to always behave.
“I have spoken to them about this. What I said was private, but it is better they go with a woman than a drink. It is better. That is what I did when I was a player.
“In Italy the players don’t have this culture to drink after the game. It is so different but I understand it is part of the English culture and it is not easy to change.
“Adam Johnson and Joe Hart are young, they are playing in the national team and they must change. It’s very frustrating for me to see this behaviour because I don’t understand it.”
He continued: “I don’t understand why a player must drink after a game. OK, maybe one drink is OK but three, four, five, six – drinking until they are drunk – this is not good.
“One day when I first started in Leicester I went with my team-mates after training to a pub and the 10 or 12 of us drank I don’t know how many beers. That wouldn’t happen in Italy after training.
“We have rules at City that the players shouldn’t drink in the build-up to games. But it is better if the player changes this themselves rather than me enforce it.”
“It is good for their career not to do this,” he added. “OK, they are young now but when you are 28 or 29 you pay the price. I don’t know if you remember Pietro Vierchowod who played until he was 40 for me at 100 per cent.
“[Javier] Zanetti at Inter Milan is 37 but is still the best player, always, because he had a good period in his life and he looked after himself.
“Maybe players in England don’t play so long but also it is hard because you play every three days and if you don’t have good behaviour off the pitch, it will be difficult to maintain a top level.
“That is why for me there can be no drinking before games. When you play every three days you must have 48 hours to recover.
“If you drink, if you don’t sleep, you can’t do it. If you are young, OK. But in one, two or three years, that will change.”