Sir Alex brain op

told the

last night: “I’ve been texting him with no reply, which is most unusual.

“He usually responds straight away. I couldn’t understand but now we know why with this sad and worrying news.”

Ferguson was United manager from 1986 to 2013, winning the Premier League 13 times and the Champions League twice.

Michael Carrick, now a United coach, said he was “absolutely devastated” and urged his former boss “to be strong.”

Similar messages were sent on Twitter by United players past and present.

Fergie’s former goalkeeper Peter Schmeichel said: “Please be strong. Win this one.”

Current Old Trafford star Jesse Lingard said on Twitter: “Thoughts and prayers Sir Alex.”

Ferguson began his playing career with Scottish club Queen’s Park as a 16-year-old.

His most notable spell as a player came in a two-year stint at Rangers from 1967.

He retired in 1974 and began his managerial career at East Stirlingshire before going to St Mirren, where he won the Scottish First Division title in 1977.

Ferguson moved on to Aberdeen and led them to three Scottish titles, four Scottish FA Cups, one League Cup and the European Cup Winners’ Cup in 1983, beating Real Madrid 2-1 in the final.

He managed Scotland in the 1986 World Cup in Mexico following the death of Jock Stein and became United boss later that year.

Everton manager Sam Allardyce said: “It is tragic. I am going to find out how he is as soon as I possibly can. I knew it was serious when I knew his son Darren didn’t attend his game at Doncaster today.

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