Lorenzo Insigne said he is not sure whether he will be fit enough for Napoli's Serie A showdown with Inter after limping off in Tuesday's loss to Manchester City.

Insigne, 26, hobbled off with an apparent thigh injury as high-flying Napoli suffered a 2-1 Champions League defeat at City.

Italian leaders Napoli will be sweating on Insigne's fitness ahead of Saturday's blockbuster against Inter, with both teams putting their unbeaten records on the line.

"I feel much better now than when I did as I asked for the substitution," the Italy international, who has scored five goals in all competitions this season, told Mediaset Premium.

"We'll see tomorrow if I'm able to play against Inter."