However, he can understand Napoli sending Osimhen to Galatasaray last week.
Cassano said on Viva En Futbol: "There are certain types of players, the phenomena, the Neymars, the Messis, the Ronaldos, where 'I'll give you whatever you want'.
"Osimhen is a strong player, but when you have a so-so season, the Hojlund or Zirkzee of the situation comes along and United goes and gets him, because he's not the champion who takes your eye off you and you say 'next year this guy risks scoring another 30 goals against me'.
"Osimhen after the championship he won you have to give him away, you have the opportunity. 130 (euros), a leg, an elbow, etc... You have to give him away. The devil wears red and what happens? He doesn't do well last year, the team is in trouble, what do you do? You give him on loan to Galatasaray.
"Then when he comes back from Galatasaray you don't have the hot potato, we're back to square one. It's true that they all lost. For me the one who lost a lot is Napoli, Osimhen is much, much stronger than Lukaku. But the coach said I want Lukaku, he said it and you take him from him."