Ronaldinho will wear the number 80 jersey at AC Milan, the club have confirmed.
The Brazil playmaker, who joined the Rossoneri from Barcelona on a three-year contract last week, had hoped to wear the number 10 shirt - his preferred choice for both Barca and Brazil.
However, that number was already taken by Dutch midfielder Clarence Seedorf, and Ronaldinho has settled for a reference to the year of his birth, 1980.
'In 23 years, we have never asked one of our players to give his number to another,' Milan vice-president Adriano Galliani told official club website www.acmilan.com.
'If the number 10 jersey had been free, it would have been a different issue.
'Alexandre Pato took the number seven jersey because Andriy Shevchenko had already left. We have never demanded or will demand any of our players to give away their number.
'We have not had any diplomatic negotiation with Clarence Seedorf regarding this issue.'