The Serie A leaders held an early lead in Naples, but City's comeback has left Sarri's men on the brink of elimination from the Champions League with six points separating Napoli and second-placed Shakhtar Donetsk.
However, Sarri had nothing but praise for his players, who he says put in a "brave" showing against opposition he describes as one of the best in Europe.
The 58-year-old is quoted by BBC Sport as saying: "I thought we were really brave tonight and we tried everything. We had to try to win and I prefer that, even if we had to take risks.
"I don't think we were too far away but we must not forget we played one of the best teams in Europe. I am very happy with the way we played technically, tactically and physically."
Napoli must win both of their remaining games - including a home clash with Shakhtar - to hold any hope of progression through to the last 16.