Zola worked with the 22-year-old when in charge of Italy's under-21 team and admits he has an affection for the striker who has had a tempestuous time at Manchester City - culminating in this week's training ground bust-up with manager Roberto Mancini.
After Watford's FA Cup defeat to City, Zola said: "I have an affection for him. I have worked with him for the under-21s and I do care about him and I do hope his potential is fulfilled.
"Even when he came on today you can see the potential in the man, and it's how to master that potential.
"I do hope he gets to that position as he will be a fantastic player. I am talking about what he can do to improve his situation but it's not down to me to say how.
"It's just that this is a young man with a lot of potential who can shine."