The incident occurred after Inter's 3-1 defeat to Sassuolo at the Mapei Stadium on February 1, 2015.
“I come on during the second half and at the 83rd minute score my team's only goal, so it ended 3-1 to Sassuolo," wrote Icardi in his book, 'Sempre avanti.'
“I am angry because I played so little. The fans start to shout: they call us to come over to their section. I find the courage to face them, along with Guarin.
“As I get closer, I receive insults and abuse of every kind. Attached to the netting is a kid who calls me: he wants my shirt.
“Considering his age, he could be my son: I take off my shirt and shorts and throw them to him, as a gift. This kid is in seventh heaven and I am pleased to see him so happy.
“A head of the ultras jumps on him to take away the shirt and throws it back at me. This is when I start insulting him: 'Piece of ****, you are acting all arrogant with a little kid to show off to the rest of the curva? Do you think you're hard?'
“In the locker room I am acclaimed as a hero, because nobody had ever faced off that way with one of the fan leaders."