But the youngster struggled to make an impression under Carlo Ancelotti, who preferred the likes of Xabi Alonso and Arturo Vidal.
He made just six starts in the Bundesliga and even dropped to Portugal's Under-21 squad despite playing a key role in their triumphant Euro 2016 campaign.
The 2017-18 race for the Scudetto is likely to be one of the best title races in Europe next season if AC Milan's summer recruitment plans are anything to go by.
The Portugal worldwide has endured a hard first season at the Allianz Arena, starting just six Bundesliga matches overall after his big-money move from Benfica.
Sanches couldn't break into Bayern's team. Adding to the arrival of Sebastian Rudy from TSG Hoffenheim as well, Sanches immediate future in Bavaria appears to be over.
Milan approached Bayern about signing Sanches on-loan, but it seems the German club would prefer a permanent deal.
Portuguese publication @Record_Portugal report that AC Milan have offered to take Renato Sanches on loan with a €47m option to buy.
The 19-year-old is expected to leave the Allianz Arena on loan this season, although the Serie A side could have the option to sign Sanches permanently for €40m in the future, according to ESPN reports.
'They reported midweek. And if you borrow a player from Bayern, that also has economic effects. "At €48m I would not be dissatisfied".
Sanches turned down Manchester United to join Bayern.