The reigning champions came from behind to beat Tottenham 2-1 at home yesterday, allowing them to go second on the Premier League table, and the Italian wants his squad to maintain that strength of character when times get tough.
"There are some moments during any season when you don't play well, you might concede goals you didn't concede last year or maybe you are missing three or four important players," said Mancini.
"At these moments it is important to stay calm and work hard. In football things can change quickly."
Man City next meet 17th-placed Aston Villa at the Etihad Stadium on Saturday, November 17.