The striker admits he's had offers to leave Serie A this summer.
"I received an important offer from the Emirates, but for me happiness is something else," Cassano said.
"The Europa League? We should be angry for the lousy injustice that we have seen. If we achieve sixth, seventh, eighth, I don't know, but we will play with great anger.
"I want to take from them what they have taken from us. I want our opponents at the Tardini to be scared of our fans."
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