5) Jack Crompton

25th May 1963. Manchester United’s Denis Law (R) and trainer Jack Crompton travel home from London by train after United defeated Leicester City 3-1 in the FA Cup Final.
When and where: Luton Town, 1962
Duration for which he was manager: 7 days
What happened?
Jack Crompton was a Manchester United goalkeeper between 1945 and 1956, and made 191 appearances for the Red Devils. He retired after the 1955-56 season, 2 years before the Munich Air disaster. Initially, Luton Town hired him as a trainer, but following the Munich tragedy, Crompton returned to Manchester United to help out the club.
In 1962, Crompton felt ready to be a manager and Luton Town again came calling. But just 7 days into his tenure, Crompton realised he wasn’t cut out for management and resigned, returning to his coaching position at Manchester United.