The Portugal attacker has joined Milan from Chelsea in a loan deal to June.
Cassano said on Viva el Futbol: “The one who excites me the most, the one who will make us happy, is Joao Felix. I like him a lot. When he left Benfica I thought that figure was exaggerated, but when I see him play, when I see how he moves, how he knows how to do one-twos.
"It’s true that he isn’t consistent, but when you see him at the stadium and he makes those quality plays, I enjoy it.
"For me he is a potential top 3 in the world wide left after Vinicius and Rodrygo. Joao Felix excites me a lot. My impression of this player is that he still has to find the right coach, who leaves him free to do what he wants. If he finds the right chemistry with the coach, he is really great stuff."