The 71-year-old Scot announced on Wednesday morning that he will stand down at Manchester United the end of the season after a trophy-laden 26-year reign, having celebrated his 49th and final piece of silverware with a 13th Premier League title this term.

Gill 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 the Manchester United board with brother Avie, pinpointed the 2008 Champions League final penalty shootout success over Chelsea as a highlight among the many memories.

He 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."

Ferguson will take on the roles of both director and ambassador for the club after stepping aside from the managerial hotseat.

Avie Glazer said: "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."

Former player Paul Ince described Ferguson as one of a kind and also admitted finding a replacement would not be easy.

Blackpool manager Ince told Sky Sports News: "He's done the lot, you will never see anyone of his kind again."

When Ince joined United from West Ham in 1989 Ferguson made sure his move was not ended because of a problem with his medical.

"I remember the first day that I joined Man Utd. I failed my medical and I thought my move to Man Utd was going to collapse. The way he treated me was like a son and I will never forget that moment.

"To play under that man was so demanding, his standards were so high. We had our ups and downs, a lot have ups and downs with him."

Ince said Ferguson's replacement would have a difficult act to follow.

"It's got to be someone with a massive character. It has got to be someone who can deal with what it takes to be a Manchester United manager.

"Whoever comes in to replace him is going to have to deal with the Man United legacy."

Ince believes Ferguson staying at the club as a director could be a double edged sword for his successor.

"It can have its advantages and disadvantages. Replacing Alex Ferguson is such a massive, massive job. Whoever goes in will need the help of Alex Ferguson," he said.

"Whoever comes in if it doesn't go well you've got Sir Alex Ferguson upstairs and it can put added pressure on you."

Professional Footballers' Association (PFA) chief executive Gordon Taylor said Ferguson would be "the toughest act to follow".

Taylor said: "The game of football will be a lot poorer place without him. He has been quite simply the best. He followed in Sir Matt Busby's footsteps and even surpassed him.

"He will be also be the toughest act to follow."

Taylor has been PFA chief throughout Ferguson's time at United and he admitted they had clashed on occasion - but that it was soon forgotten.

He added: "I will miss him - he has been a very good friend of the PFA throughout his career.

"Of course at times it has not always been smooth and we have had a difference of opinion but we always respected each other and we have had a lot more agreements than disagreements.

"He is a great football man, he has turned out team after team and in terms of youth development he has been one of the finest exponents of that. He has had a faith and a belief in his youngsters that is rare in today's football."

Former United striker Dwight Yorke, who played under Ferguson between 1998 and 2002 and was part of the 1999 treble-winning side, feels a combination of factors led the Scot to call it a day at the age of 71.

"I've seen Sir Alex Ferguson on Monday at a charity game," the former Trinidad and Tobago international told Sky Sports News.

"He was in good spirits but the rumours were really strong around the place that he was going to retire and there was a big announcement supposed to be happening tomorrow and not today.

"I think probably the fact of the club floating on the stock market meant this decision needed to come out very quickly. But the people within the football club knew this was likely to happen this season. And I think with his hip replacement (booked in for late July), with David Gill going as well, that sort of pushed him to say 'this might be the best time for me to retire'."

Yorke expects there to be a strange atmosphere in the immediate wake of Ferguson's departure from the helm.

"He's been such a focal point at the football club," he said. "He's taken Manchester United to the level they are at right now.

"It's a shock to the system because he's been there every day. He's the one person when you go into the football club he's always there. For him not to be there from the start of next season, it's not going to be right around the football club and it will take some getting used to."

Ferguson, of course, will be bowing out on a high having regained the Premier League title after being pipped to the crown by rivals Manchester City in dramatic circumstances on the final day of last term.

"He has very, very high standards and it's all about winning trophies and breaking records with Sir Alex Ferguson," Yorke continued.

"But there's more to the man. How they lost the Premier League last season - that would have hurt him immensely. Certainly losing it to Manchester City, that would have hurt worse than anything else.

"He wanted to regain it and he's managed to do that in a great way and with a great style of play."

FIFA president Sepp Blatter, who gave Ferguson with a lifetime achievement award last year, said on Twitter: "Just heard Sir Alex Ferguson is retiring at end of season. His achievements in the game place him without doubt as one of the 'greats'."

Sports minister Hugh Robertson also paid tribute, saying: "Sir Alex Ferguson is one of the greatest British managers of all time and has been an incredible servant to Manchester United, bringing the club unprecedented success domestically and in Europe.

"His enthusiasm for our national game is boundless and I congratulate him on a remarkable managerial career."

United confirmed the news on their website on Wednesday morning.

"The decision to retire is one that I have thought a great deal about and one that I have not taken lightly," said Ferguson.

"It is the right time."

Ferguson's last game in charge will be at West Brom on May 19 and he will join the club's football board.

"It was important to me to leave an organisation in the strongest possible shape and I believe I have done so," he said.

"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."

Ferguson has had a career the like of which will never be seen again. He won his 49th trophy in United's 20th league championship and seemed set to extend his career into next season, confirming as much in his programme notes ahead of Sunday's encounter with Chelsea.

Instead, with a hip operation booked in for August, this weekend's Old Trafford encounter with Swansea, that will be followed by a trophy presentation, will be his last home game in charge.

He leaves behind a club in good shape.

"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," said Ferguson.

"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.

"I must pay tribute to my family, their love and support has been essential.

"My wife Cathy has been the key figure throughout my career, 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."

Although there have been times - in 1989 when it seemed he was going to be sacked, and 2002, when he was about to retire and instead performed a last-minute U-turn - when it was felt Ferguson was ready to leave, this time it is permanent.

The speculation intensified on Tuesday afternoon and United's failure to respond to questioning about the matter further fuelled the rumours overnight.

Now, Ferguson is left to look back on the power-shift in English football that he has instigated.

"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," said Ferguson.

"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."

Now, for the first time in over a quarter of a century, United are on the hunt for a new manager.

David Moyes, out of contract at Everton, and Jose Mourinho, who is expected to leave Real Madrid at the end of the season, are the obvious favourites, although Borussia Dortmund's highly-regarded coach J?rgen Klopp and Bayern Munich's 67-year-old outgoing boss Jupp Heynckes will also come into contention.

It promises to be a major test of nerve for the Glazer family, plus Ed Woodward, who will replace David Gill as chief executive in the summer.

"Alex has proven time and time again what a fantastic manager he is but he's also a wonderful person," said co-chairman Joel Glazer.

"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."

Avi 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."

Ferguson's exit coincides with that of Gill, who hopes to be voted onto UEFA's executive committee in the summer.

"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," said Gill.

"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."

Source: Foxsoccer