The pair are as mad as hatters with Balotelli world renowned for his wacky antics, including setting fire to his bathroom with fireworks and walking into a school full of children and asking for the toilet.
Former wild-man Cassano has calmed down slightly now he is married with a child but he loves nothing better than dancing around the pitch in only his underpants after a big game.
Thursday's match is no laughing matter, though, and coach Cesare Prandelli is considering splitting the duo up after forward Antonio Di Natale replaced Balotelli off the bench to score in the 1-1 draw with Spain in their group opener.
Croatia, who beat Ireland 3-1 in their first match, pose a very different threat to Spain given their aerial prowess and Prandelli must decide if Balotelli's strength and height outweigh the fact he struggled against the holders.
"He is a guy of 22 years of age, he is on the road to finding maturity. What I ask is for him to play simply. To help the team and to stretch the play behind the opposition defence," Prandelli told reporters while reflecting on Balotelli's bad miss against Spain when he was caught in two minds and tackled.
"When he makes a mistake he must think that there will be other opportunities...and find the conviction to make the right decision next time.
"The thing to underline is that he won the ball himself [in that chance]. When you have two choices it slows you down."
"I want to understand who is most tired," said Prandelli, whose forwards are all on the small side except for Balotelli.
"We will be more relaxed and not under such pressure after the opening victory, but it can't be much better than this in the next game," he said.
"Italy are strong, they think about us and about our play. Prandelli respects us. They have a team and players who can dominate on the pitch. For me, they are not weaker than Spain, especially with Prandelli in charge."
