Manchester United have confirmed that Sir Alex Ferguson will retire at the end of the season after winning the club's 20th league title and will move upstairs to become a director and ambassador.
Ferguson, 71, took charge of United in 1986 and enjoyed a trophy-laden 27 years at the club. United have dominated English football in the Premier League era, winning the title 13 times and also lifting the Champions League in 1999 and 2008.
In addition, he won the FA Cup five times, the League Cup four times, plus the FIFA Club World Cup, Intercontinental Cup, the UEFA Cup Winners' Cup and the UEFA Super Cup.
His final match will be against West Bromwich Albion on May 19, his 1500th game in charge of United.
He won an unprecented 49 trophies in total, the frst coming when St Mirren won the Scottish First Division title in 1976-77. He then moved to Aberdeen and turned the Dons into a European force in the 1980s. There he won three championships, four Scottish FA Cups, the League Cup, the UEFA Cup Winners' Cup and the UEFA Super Cup.
A statement released to the New York Stock Exchange on Wednesday morning stated: "Sir Alex Ferguson will retire at the end of the season, Manchester United announced today. The most successful manager in English football history will bow out after the West Bromwich Albion game on 19 May and join the football club board."
Announcing his decision to retire, Ferguson spoke of his pride at his achievements at United and also thanked the club for allowing him to rebuild it from top to bottom.
"The decision to retire is one that I have thought a great deal about and one that I have not taken lightly," he said. "It is the right time. It was important to me to leave an organisation in the strongest possible shape and I believe I have done so.
"The quality of this league winning squad, and the balance of ages within it, bodes well for continued success at the highest level whilst the structure of the youth set-up will ensure that the long-term future of the club remains a bright one.
"Our training facilities are amongst the finest in global sport and our home Old Trafford is rightfully regarded as one of the leading venues in the world.
"Going forward, I am delighted to take on the roles of both director and ambassador for the club. With these activities, along with my many other interests, I am looking forward to the future, providing a bedrock of both stability and encouragement. Words are not enough to express what this has meant to me.
"As for my players and staff, past and present, I would like to thank them all for a staggering level of professional conduct and dedication that has helped to deliver so many memorable triumphs. Without their contribution the history of this great club would not be as rich.
"In my early years, the backing of the board, and Sir Bobby Charlton in particular, gave me the confidence and time to build a football club, rather than just a football team.
"Over the past decade, the Glazer family have provided me with the platform to manage Manchester United to the best of my ability and I have been extremely fortunate to have worked with a talented and trustworthy chief executive in David Gill. I am truly grateful to all of them.
"To the fans, thank you. The support you have provided over the years has been truly humbling. It has been an honour and an enormous privilege to have had the opportunity to lead your club and I have treasured my time as manager of Manchester United."
United chief executive David Gill, who will himself leave the club this summer, said: "I've had the tremendous pleasure of working very closely with Alex for 16 unforgettable years - through the Treble, the double, countless trophy wins and numerous signings. We knew that his retirement would come one day and we both have been planning for it by ensuring the quality of the squad and club structures are in first class condition.
"Alex's vision, energy and ability have built teams - both on and off the pitch - that his successor can count on as among the best and most loyal in world sport.
"The way he cares for this club, his staff and for the football family in general is something that I admire. It is a side to him that is often hidden from public view but it is something that I have been privileged to witness in the last 16 years.
"What he has done for this club and for the game in general will never be forgotten. It has been the greatest experience of my working life being alongside Alex and a great honour to be able to call him a friend."
Joel Glazer, joint chairman of United along with his brother Avie, said: "Alex has proven time and time again what a fantastic manager he is but he's also a wonderful person. His determination to succeed and dedication to the club have been truly remarkable. I will always cherish the wonderful memories he has given us, like that magical night in Moscow."
Avie Glazer added: "I am delighted to announce that Alex has agreed to stay with the club as a director. His contributions to Manchester United over the last 26 years have been extraordinary and, like all United fans, I want him to be a part of its future."
Reports about Ferguson's retirement emerged in the Daily Telegraph late on Tuesday, the news coming just days after the club announced he was likely to miss the start of the 2013-14 season after hip surgery.
Bookmakers have closed markets on Everton manager David Moyes being his immediate successor after a flurry of bets on Tuesday.
United have long been attempting to put a framework in place so that the succession is as smooth as possible - and avoids the chaos of the post-Matt Busby era, when the legendary manager moved into a director of football role before later returning to take the managerial reins.
A pre-Christmas board meeting led to an understanding that Ferguson would not leave until 2015, and Ferguson recently stated that he will not be vacating his position with the Red Devils anytime soon. But Sir Alex has decided to step down later this month.
However, there have already been informal meetings with potential future candidates. Ferguson, David Gill and one of the Glazer family met Pep Guardiola in New York in October, before the Catalan agreed to take over at Bayern Munich.
Despite Ferguson's personal enthusiasm about the future appointment of Guardiola, he is known to have been a huge admirer of Moyes and feels he has many of the qualities necessary to take over at Old Trafford.
Jose Mourinho is not expected to be in the frame, though, with a high-ranking Stamford Bridge source telling ESPN that the Portuguese is "virtually certain" to replace Rafael Benitez in the next two months, and there is too little leverage room for United to attempt any kind of late high-profile coup. However, it is understood that Roman Abramovich is balking at paying any buy-out clause, which may leave an opening for United.
Ferguson announced his intention to retire in 2002 before changing his mind and going on to win a further six Premier League titles, with this year's championship crown his 13th in all with the club.