Lookman released a statement on Wednesday declaring himself "hurt" and accusing his coach of being "disrespectful" after Gasperini had slammed the Nigeria striker after he failed from the penalty spot in their Champions League defeat to Club Brugge.
“It is human to make mistakes, including from the penalty spot,” said Del Piero on Sky Italia.
“Aside from the internal dynamics of that team, I would have been very upset by Gasperini’s words in the press conference. I am therefore not entirely surprised that Lookman responded that way, as he is right to do so.
“He is having an extraordinary campaign and has been put on the chopping block, which risks damaging the rest of the season. We’ll see how the team reacts.”