City remain unbeaten in their title defence and have not lost at home in the League for 37 matches, a run stretching back to a defeat to Everton two years ago.
Yet Everton remain a recurring problem for City, having lost eight of their 10 previous games against the Merseysiders.
Mancini said: "Everton is always a difficult game because they work hard, they defend very well.
"In the second half we played better, probably deserved to score another goal.
"In the end we are not happy but the season is long and this doesn't change anything.
"If you don't pay attention you can lose three points and it is sometimes better to take one."