But he (or his ghost writter) comes out of the shell in his autobiography.
So much so, he says his time playing for England was a bit of a nightmare ... and he was "scarred" by Keegan!
Owen: "A team meeting was called to discuss the Romanians and Keegan set off on a 20-minute lecture about me. 'Michael, if I was any other manager you would not be playing tomorrow.
"You've got to improve or we'll have to change.' I really started to resent him - not as a man but as a manager. With a quarter of an hour gone I thought, 'Sod him, I'm playing my own game. I know I'm good.' Then I scored and the relief was immense.