Sir Alex's retirement was not the only secret kicking around at the back-end of the season as we can reveal that Prince William made a private and informal visit in April to tour the facilities and meet Sir Alex, David Gill and the Reds' first-team squad.
The Prince, who is a self-confessed Aston Villa fan, visited the training ground on 15 April just a week before the Reds routed Villa to seal a 20th championship title.
For the last seven years, he has held the title of President of the Football Association, where the club's outgoing chief executive Gill holds the position of vice-chairman.
The Duke of Cambridge was accompanied by his communications secretary Patrick Harverson, who, prior to joining Clarence House, worked at United.
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