The Euro 2020 qualifying campaign kicks off on Saturday.
Mancini said, “We'll see who plays tomorrow.
"I expect Kean to do what he does best. He doesn't have Insigne's experience, but does bring physicality, enthusiasm and an eye for goal. We hope he'll bring joy to the team."
He added: “Euro 2020 qualification was the primary objective and we honoured the Nations League to the end, but from tomorrow it becomes fundamental not only that we win, but also improve our ranking and potential draw going forward. We'd like to improve our ranking, as the current picture isn't one we like very much."