The youngster rose to the side's senior set up during Allegri's spell at Milan before being moved on during last season only for Seedorf to see the sack as well at the end of the season.
And while the unofficial new coach Filippo Inzaghi wants to integrate his new team on youth with the likes of De Sciglio, Balotelli, El Shaarawy, Poli and Cristante as the foundation of the team, a bid of around 20 million euros could be enough to tempt the club into a sale as president Berlusconi is no longer putting money into the club.
And Milan would have a back-up plan to the departure of De Sciglio with Newcastle's Davide Santon touted as a replacement and could arrive with Niang going the other way.
Ancelotti would be obviously enticed by the prospect of De Sciglio joining the Spanish club as he is able to play in any spot in the defence but prefers the flanks, namely the right side. He would also represent an upgrade to Arbeloa and probably Carvajal too.
The next couple of months will be sure to define AC Milan as they look to either rebuild around their youth or decide to sell and bring in lesser players and firmly remain as a club in decline.