An AC Milan fans' group has told Gianluigi Donnarumma they will forgive him if he fires agent Mino Raiola and signs a new contract.
Last week, Raiola told the club that the 18-year-old goalkeeper, who has a year left on his contract, would not be signing a new deal.
But Milan are refusing to sell Donnarumma and have threatened to leave him on the bench for a season.
A statement on the website of the Milan fans from the Curva Sud at the San Siro said: "We know that the last few days must have been difficult, to defend himself from the criticisms and insults he will have received, but when you make vows of love and betray them this is the only way the situation can be.
"Obviously we do not condone any threats, which have nothing to do with the position we are taking.
"Football today is even further detached from people's passion and even closer to people like Raiola; people who are capable of influencing an entire career and clubs' histories without scruple, with just one interest -- their own.
"We still believe there is a chance to put things right, but now it depends on you withdrawing from your affairs with the person who has pushed you to do wrong and ruined your image."
Donnarumma is on international duty with Italy's under-21s, but has not escaped criticism in Poland.
During the opening group game against Denmark on Sunday, fake dollar bills were thrown at him and a banner bearing the name "Dollarumma" was hung behind his goal.
On Monday, Raiola said Milan were responsible for Donnarumma's decision not to extend his contract, but the Milan fans' group said only the agent could be blamed.
"We find it strange that such a competent agent is unable to act in the best interests of his client but has instead destroyed his image in the eyes of all football fans, who now discover that an 18-year-old can show no respect towards the club who launched his career just because of the interest of a man behind him who is promising him mountains of money," the statement said.
"For a sportsman the appreciation of your people has no economic value, and we invite Donnarumma to reflect on what he has deprived himself of for his future career."