Gianluigi Donnarumma should stay with AC Milan and end the transfer saga unless he wants his poor performances at the European Under-21 Championship to continue, says Dino Zoff.

Italy legend Zoff was unimpressed by Donnarumma's international displays as the Azzurrini ultimately suffered defeat to Spain in the semi-finals.

The 18-year-old has been involved in a major off-season drama since rejecting an offer to extend his San Siro contract beyond 2018, the Serie A side claiming their proposal was worth €50million over five years.

Donnarumma, who deleted his Instagram account and claimed it was hacked during the Euros after a string of mixed messages on social media, is due to meet with Milan to hold discussions on his future now the tournament is over.

The goalkeeper had fake money thrown at him by angry supporters during Italy's match against Denmark at the Euros and Zoff feels his head was clearly elsewhere as he called on him to commit to Milan.

"That kid is not calm, you can see it a mile away," Zoff said to Corriere della Sera. 

"I think he has got himself involved in a bigger mess than he can handle, just look at what he did in the Euros. He was not good for the whole Euros.

"Unfortunately, I expected it, because after the storm that erupted around him in the media I would have been agitated when I was 40 years old, so imagine it for him.

"He should just be focused on playing, growing and improving. Massimiliano Allegri was right when he said kids need to be on the pitch as much as possible so they can learn from their mistakes. Like everyone, Donnarumma makes mistakes and he will make many more, especially if he doesn't resolve this story quickly.

"You could tell in Poland that his mind was elsewhere. You didn't need to be a goalkeeper to tell he lacked his usual quick reactions, but that was only natural in the circumstances.

"My advice is to stay at Milan. He can grow there on a human and a professional level. It is the right choice and the only thing he can do to get back on track in the maturation process."

Real Madrid and Juventus have been among the clubs linked with a big-money move for Donnarumma.

Zoff said: "He would fit in well there or at any big team - but later, not now. He must understand he has his whole life ahead of him to play for Real Madrid, Barcelona, Juve or wherever he wants to play.

"He has the ability, the character and age on his side. He must realise he is 18 years old and that is his greatest asset, because being that age means you are in no rush for anything.

"At 25 or 30, you are sometimes forced into decisions because you are calculating the time left in your career, but he is a kid and he does not have to think about money. Donnarumma must have patience – if he does, everything will be fine.

"In football you are only what you give on the pitch day by day, not the autographs you sign, the salary you earn or the valuation your agent puts on your head."

On the teenager's reported price tag of over €100million, Zoff added: "Everything has taken on absurd dimensions. I wonder if this system will be sustainable for a long time? I have my doubts."