Jorge Jesus has been appointed head coach of Benfica for a second time after leaving Brazilian and South American champions Flamengo.
Benfica have turned to veteran Portuguese boss Jesus after they were dethroned by bitter rivals Porto in Primeira Liga this season, it was announced on Friday.
Flamengo had been hopeful of keeping Jesus, who led the club to Campeonato Brasileiro, Copa Libertadores and Recopa Sudamericana glory following his arrival last year.
However, Jesus has re-joined Benfica, where he previously spent six years and won three league trophies among other honours in Lisbon.
"Despite regretting the loss of their victorious coach, Flamengo respects this personal decision," Flamengo said in a statement.
"On behalf of the entire board and the 42 million red-blacks who make up the biggest fan club in the world, our greatest thanks to him and all his technical committee for everything that has been done and our wish that they continue to maintain the enormous success as had with us.
"Flamengo, following what its anthem advocates - and which Jorge Jesus represented so well - will continue in its usual goal: Win, win, win!"
After winning a second Libertadores title and first since 1981 in November, Flamengo were crowned Brazilian champions for the seventh time last year, having not claimed the Campeonato Brasileiro since 2009.
Flamengo then added the Recopa – which pits the Libertadores and Copa Sudamericana champions against each other – to their collection in February.
Rio de Janeiro giants Flamengo also wrapped up the Carioca state championship title against Fluminense on Wednesday.
Jesus, 65, wrote via Instagram: "It was 13 months of perfect union, a time when I was very happy, I felt at home, we had unforgettable achievements. But today we met with the Flamengo board and decided that it was time to end our relationship, without hurting, resentment.
"A break that will leave no scars, only memories of victories and titles, emotions that I will carry for life. End of a cycle, the time has come to return to Portugal. Flamengo, I am sure, will follow its victorious trajectory because it has a cast and structure that matches its greatness.
"To the club, its board and its employees, to this fantastic group of players, to the fans of Flamengo, my eternal gratitude, you will remain forever in my heart."