AC Milan announced that the club have completed the signing of Sandro Tonali from Brescia.
The midfielder joins on an initial season-long loan for a fee of €10 million (£9m/$12m) with the option to buy him outright for €15m (£14m/$18m) next summer.
In total, the deal could be worth up to €35m (£32m/$41m) including add-ons, as Milan have sealed a deal for one of Italy's most talented midfielders.
“We are excited to welcome Sandro to the Rossoneri family," said club legend and current technical director Paolo Maldini.
"As a talented, young midfielder he will not only embrace the values of AC Milan but also make a significant contribution to the future success of the club."
Tonali, who has earned three caps for the Italian national team, made 89 appearances and scored six goals over three seasons with the Brescia first team.
Tonali has been compared to former AC Milan star Andrea Pirlo, with the now-Juventus boss buying into the hype himself by saying that Tonali is a more complete player than he was at that age.
The 20-year-old Tonali, who will wear the No. 8 jersey, all but confirmed the move on Tuesday as he confirmed his childhood fandom of the club by posting a photo of him wearing a Milan shirt as a child.
"We are delighted to welcome Sandro Tonali to AC Milan," said the club's CEO Ivan Gazidis. "He is one of the most promising young talents in international football.
"Sandro has a love for the club and an understanding of its values that will add to what we want to build together. Welcome Sandro!"
Milan are set to face Shamrock Rovers on September 17 in the second qualifying round of the Europa League.
After that, the club will look ahead to opening the season four days later at home against Bologna.