It is to Manchester United's benefit that their new manager knows all about taking over a once-great club which is dining out on past glories and drowning in its own exceptionalism.
'There's an air of, "We know it all", at the club,' he said after taking over at Ajax in 2017. 'They've lingered too long on their historical triumphs. Something has to happen but in Amsterdam it's not that simple.'
Something did happen. Ten Hag broke away from the club's favoured 4-3-3 formation - an article of faith since the days of Johan Cruyff and Total Football - and, in partnership with director of football Marc Overmars, turned the club into Dutch champions and Champions League semi-finalists.