The former Santos star has been linked with a move back to his old club for some time, and the 2011 Copa Libertadores champions were keen on bringing him back.
According to Brazil's Globoesporte, talks had progressed positively over the past few days and Santos were ready to send representatives to Italy, but Milan have decided to reject the club's proposal.
According to this report, Santos would have paid four million euros and have given Milan goalkeeper Rafael, who would have remained on loan at Santos for the season. However, Milan do not seem interested in the 22-year-old, who has been a fixture in the Peixe lineup since 2010 and is now starting to break into the Brazilian national squad.
Milan's apparent lack of interest in such a deal could stem from their May acquisition of 19-year-old Brazilian keeper Gabriel, who many believe will be a regular in the squad in a couple seasons. It could also be that Milan want only money in order to help balance the books and replace Thiago Silva and Zlatan Ibrahimovic as Milan look to go younger.
The odds of Robinho being a Milan player at the start of the season continue to diminish, but if Santos or any other club in Brazil want the Brazilian star, they have to act quickly to make it happen. The Brazilian transfer window closes in five days.