James Horncastle of BBC Sport and ESPN confirmed the hire by the Rossoneri:
The decision to hire Seedorf, who was immediately viewed as the favorite to land the job, comes shortly after Milan announced they had parted ways with Allegri:
AC Milan wish to communicate that Massimiliano Allegri and his staff have been relieved of their duties with immediate effect.
AC Milan would like to thank Mr. Allegri and his staff for their time with the club and wish them the best for the future.
Following the move, the Seedorf camp, led by agent Deborah Martin, made it clear he was free to get out of his contract with Botafogo if chosen to become the new Milan manager.
Nadia Carminati of Sky Sports passed along the comments Martin made to Italian outlet La Gazzetta dello Sport about the step the longtime midfielder had already taken:
I personally negotiated the contract when Clarence signed for Botafogo and he has a clause in his contract that allows him to leave the club without compensation on certain occasions, as long as he doesn't play for another team.
I would also like to point out that Clarence now has all the necessary papers to coach and has taken all the steps needed in Netherlands and Brazil.
Eurosport provided historical context surrounding Seedorf's hiring:
As a player, Seedorf made stops with Ajax and Sampdoria before making a major splash with Real Madrid. From there he moved to Inter Milan and eventually AC Milan, where he enjoyed his longest stay with any club, from 2002 until 2012.
Since leaving San Siro he's continued to play with Brazilian side Botafogo, but he finally appears ready to put his playing days behind him for a chance to manage his former club.
The 37-year-old Dutch star certainly doesn't lack match experience. He's played countless big games throughout his career in various leagues, European competitions and international duty with the Netherlands since his debut in the early 1990s.
However, taking over a club like Milan that has struggled in Serie A play during the first half of the campaign is certainly a new kind of test for Seedorf. Usually, first-time managers build their way up the ranks before taking over a high-profile job like Milan, but he's jumping right into the fray.
His playing experience, understanding of the Milan culture and ability to lead as a player make him a promising selection with obvious upside. That said, he's still a rookie boss entering in the middle of a season in which the club has underperformed.
Not everybody believes it will be a success. Stefan Coerts of Goal.com provided remarks from Zvonimir Boban and Fabio Capello, both of whom raised concerns about Seedorf's readiness:
"I hope for Milan and for Seedorf himself that he doesn't become Milan's coach. He's not ready for it," former Rossoneri star Zvonimir Boban recently stated, an opinion supported by coaching legend Fabio Capello.
"Evidently his time in Brazil is serving him well, but to immediately take the responsibility of the Milan job is something else," the current Russia boss stressed last month.
Those fears apparently weren't enough to persuade Milan to look in another direction.
Ultimately, it's a high-risk, high-reward appointment that could see the Rossoneri land the next great manager. There's also a chance he's not ready to lead a club like Milan, which would cause even more problems than the side is already dealing with.
Only time will tell how it all plays out.