Napoli doctors are confident Lorenzo Insigne's injury is not serious.

Insigne was released from Italy's squad carrying a knock to his knee.

“Insigne is fine, he's in decent condition, but at this moment cannot complete a training session 100 per cent," Napoli medic Alfonso De Nicola told Radio Kiss Kiss.

“He has no big problems with his knee and Doctor Castellacci treated him very well in the Italy camp. Lorenzo simply returned so as to avoid running any risks. It was pointless him staying there, as he couldn't have played.

“He is working towards returning to training with the group on Tuesday. Our objective is to ensure he doesn't lose form and absorbs the two traumas.

“I am super optimistic and believe Lorenzo will be available for the game against Fiorentina."