Claudio Ranieri insists Gianluigi Donnarumma is not chasing money and believes a move to Real Madrid would demonstrate the goalkeeper's ambition as the saga surrounding his AC Milan contract continues.
Donnarumma, who deleted his Instagram account and claimed it was hacked last week after a string of mixed messages on social media, is due to meet with Milan to hold discussions on his future now that Italy are out of the European Under-21 Championship.
Madrid are one of the clubs to be linked with the 18-year-old after he rejected an offer to extend his San Siro contract beyond 2018, the Serie A outfit claiming their offer was worth EUR50million over five years.
Donnarumma had fake money thrown at him by angry supporters during Italy's match against Denmark at the Euros in Poland this month.
But Ranieri, former head coach of Milan's city rivals Inter as well as the likes of Juventus, Roma and Napoli, is on the side of Donnarumma and his controversial agent Mino Raiola.
"I am with Donnarumma and Raiola," new Nantes boss Ranieri told Gazzetta dello Sport.
"This is nothing to do with money and it is ridiculous to talk about a betrayal.
"The crux of the problem is that the player will only renew his contract if he believes in the relaunched project presented by the new Rossoneri ownership.
"Raiola said long ago, 'A talent like Donnarumma deserves to be part of a great team'. Are Milan on the level of the five or six leading European teams?
"It is not about money because the offer from the Rossoneri leaders is excellent. It is a matter of ambition, a professional career path.
"If Donnarumma went to Real Madrid he would probably win two or three Champions Leagues in the next 10 years, right?
"It is normal to have doubts, yet they accuse him of being a traitor. If he stays, it will be a tremendous act of love for the Rossoneri world."