The Giallorossi have spent the last few days in a training camp in Disney World and crushed local team Orlando City 5-0.
"The Americans tried to base the game on grit and determination, but we did well to focus on playing football and overcome them," said the Italian international midfielder.
"We are in good shape and proved that today. We know how to play football and can do similar things against Napoli.
"We know it won't be easy, but we will not be tired on Sunday evening."