Sir Alex is one of the most quoted men in football: and when he speaks, you listen. Here are some of our favourite quotes from over the years...
"Part of my job is to make sure these lads keep their feet on the ground. I hammer it into them that the work ethic is what got them through the door here in the first place, and they must never lose it. I say to them, ‘When you go home to your mother, make sure she is seeing the same person she sent to me, because if you take all this fame and money the wrong way, your mother'll be disappointed with you'."
"I never give in or give up easily on either a player or a cause. Even if the team have won, I’m not always happy because standards are all-important to me and, if they have dropped, I’m angry."
"We don’t give in, we play right to the end. It’s not an accident: it’s part of the make-up of the team."
"This team might not have the Ronaldo factor, but it doesn’t understand the word defeat."
"When an Italian tells me it’s pasta on the plate I check under the sauce to make sure. They are the inventors of the smokescreen."
"I can’t believe it. I can’t believe it. Football. Bloody hell."
On press concerns over Wayne Rooney’s temper in 2004: "What were you like when you were 19? I was trying to start a workers’ revolution in Glasgow. My mother thought I was a Communist."
"Pippo Inzaghi – that lad was born offside."
"It’s getting tickly now – squeaky-bum time, I call it."