Former Netherlands and AC Milan midfielder Clarence Seedorf will become the Serie A club's new coach after announcing an end to his illustrious playing career in Rio de Janeiro.
Seedorf left Milan for Brazil's Botafogo in 2012.
Although the 37-year-old Dutchman has no previous coaching experience, he said he was retiring as a player.
"I am here to announce that I am going to stop playing football. I am going to retire after 22 years. It was a difficult night, but I am satisfied with what I have done in my career and what I managed to do here with Botafogo," Seedorf said.
Seedorf's agent Deborah Martin said he had signed a two-and-a-half year contract to replace Massimiliano Allegri, who was fired by Milan on Monday following a dismal run of results for the seven-times European champions.
The now retired midfielder added that his recent experience would help him with his next challenge as coach.
"This is not a goodbye, for sure we will meet again. All of the experience over the last year and a half is going to help me in my next step, which is to be the coach of Milan," Seedorf said.
The move to appoint Seedorf, who had a successful 10-year playing career at Milan, is something of a gamble although he is a hugely popular figure at the club and should arrive with a deep bank of goodwill.
The midfielder was the first player to win the Champions League with three different clubs - Ajax Amsterdam in 1995, Real Madrid in 1998 and AC Milan in 2003 and 2007. He has also represented Inter Milan and Sampdoria.
The former Dutch international won two league titles and an Italian Cup to go with the two Champions League victories during his time at Milan, during which he was also awarded the UEFA Best Midfielder Award in 2007.
Seedorf joined Botafogo in 2012 on a two-year contract the club said was the best ever given to a foreign player.
His drive and often admired professionalism helped turn the club's fortunes around and 2013 was their most successful season in years.
Botafogo won the Rio state championship in May and finished fourth in the Serie A, a placing that took them into the Copa Libertadores, South America's version of the Champions League, for the first time since 1996.