Sir Alex Ferguson is in intensive care after undergoing emergency surgery following a brain haemorrhage.

Rumours began to circulate about the 76-year-old’s health after Doncaster manager Darren Ferguson, Sir Alex’s son, did not attend his side’s final match of the season against Wigan because of what was reported as a “severe family issue”.

Manchester United announced the news in a brief statement on Saturday evening, adding: “The procedure has gone very well but he needs a period of intensive care to aid his recovery. His family request privacy in this matter. Everyone at Manchester United sends our very best wishes.”

Ferguson had a prolific career as a striker in Scotland but it was when he entered management that his true talent in football became clear.

After transforming St Mirren, Ferguson took over the hot-seat at Aberdeen and guided them to the European Cup Winners’ Cup in 1983, beating Real Madrid in the final.

Ron Atkinson’s sacking led to Ferguson taking over at Old Trafford in November 1986. Famously, success did not come immediately, and football folklore has it that Ferguson was nearly shown the door himself before an FA Cup triumph in 1990 paved the way for an unprecedented two decades of glory.

The highlight, of course, was United’s treble of Premier League, Champions League and FA Cup in 1999, and he went on to achieve more European glory in 2008 as well as 13 league titles.

Well wishes immediately flooded in for the most successful manager in the history of the British game, who had appeared fit and well when he presented his old sparring partner Arsene Wenger with a memento at Old Trafford last Sunday ahead of the Frenchman’s departure from Arsenal.

The Football Association, Premier League, FIFA, UEFA and individual clubs from Britain and around the world all tweeted their best wishes along with a host of current and former United players. The Scot retired in May 2013 after winning 38 trophies during 26 and a half years as manager.

David Beckham posted a picture on Instagram of him signing a contract as a teenager alongside Ferguson, accompanied by the message: “Keep fighting Boss.. Sending prayers and love to Cathy and the whole family x @manchesterunited”

Former United striker Wayne Rooney wrote on Twitter: “Get well soon Boss. Thoughts with all the family at this sad time. #AlexFerguson”

Another former United player, Real Madrid’s Cristiano Ronaldo,. tweeted: “My thoughts and prayers are with you, my dear friend. Be strong, Boss!”

United club captain Michael Carrick said on Twitter: “Absolutely devastated to
hear about Sir Alex being unwell in hospital. All my thoughts and prayers are
with him and his family. Be strong Boss.”

Ashley Young, whom Ferguson brought to Old Trafford in 2011, said on Twitter:
“Gutted to hear the news tonight about Sir Alex. Don’t really know what else to
say other than thoughts and prayers with you and your family, Boss.”

Mike Phelan, who played under Ferguson for United and later served as his
assistant manager, said on Twitter: “#SirAlex You’ve won more than most and if anyone can you can boss.”

Forward Jesse Lingard said on Twitter: “Thoughts and prayers sir alex,” left-back Luke Shaw tweeted: “Sending my love and best wishes to sir Alex,” while former goalkeeper Peter Schmeichel wrote : “Please Be strong Win this one.”

News of Ferguson’s condition emerged after Everton’s Premier League draw with Southampton.

Saints boss and former United striker Mark Hughes said: “I only just got a little whisper earlier on. I was hoping it wasn’t true. I wish him all the best.”

Everton manager Sam Allardyce, a long-time friend and adversary, said: “It is tragic. I am going to find out how he is as soon as I possibly can. Obviously I knew it was extremely serious when I knew his son Darren didn’t attend his own game at Doncaster today.

“I hope he is in good hands and I hope the operation is a major success
because as a personal friend… I hope he has a full recovery.”

Ferguson also received good wishes from Scottish First Minister Nicola Sturgeon and Scottish Conservative leader Ruth Davidson.

Sturgeon said on Twitter: “My thoughts are with Alex Ferguson and his family – wishing him a full and speedy recovery.”

Davidson tweeted: “So many people will be wishing Alex Ferguson well and sending their thoughts to his family tonight.”