Sarri said: "You are more competitive in the market, or you have to work. I don't know another way.
"I think we need only to work and we have to try to reduce the gap because at the moment there is a gap.
"Here it's really very difficult. The Premier League is very competitive. It's not easy to win, it's not easy to get (into) the Champions League.
"We need to work, but I think they (City) are an example for every club."