In a professional career spanning 33 years, Ten Hag had never visited Old Trafford before. He sat in the away dugout at the Etihad 13-and-a-half years ago, appropriately dressed in a black suit, white shirt and red tie, next to Steve McClaren.
Ten Hag pressed the flesh of so many people at the 112-year-old stadium on Monday he might have felt like the Queen during the Platinum Jubilee celebrations.
As anyone who has embarked on a tour there, Old Trafford is a labyrinthine of corridors and Ten Hag's visit took in all four stands.
He visited staff in the east stand offices above the Megastore that overlook the Trinity statue, the museum and tour in the Sir Alex Ferguson stand, addressed the press in the Sir Bobby Charlton Stand and entered the plush home dressing room in the Stretford End.
Step outside the home dressing room and a few steps down the corridor is the manager's office, still off-limits to supporters guided around Old Trafford.
Inside, monochrome portraits of the United managers adorn the wall. Ole Gunnar Solskjaer has already been framed and it is a wall Ten Hag studied pensively. He will not want to join it any time soon.
Ten Hag marvelled at the immortalisation of Best, Law and Charlton on the forecourt, his agent Kees Vos standing nearby, and respectfully took in the Munich clock and tunnel. Whilst embracing United's history, Ten Hag told staff he intends to create his own and not be burdened by it as some of his predecessors were.
On the pitch, the groundsman Tony Sinclair was preparing for next season. Sinclair has demonstrably improved the pitch since replacing Keith Kent in 2001, been named the club's employee of the year multiple times and the Old Trafford pitch has been recognised as the Premier League's best.
Staff at United urged Sinclair to accept interview requests but he is reluctant to divulge the secrets of his success. Ten Hag was particularly pleased to meet a potential unsung hero who may ease the team's identity crisis.
Sources say Ten Hag created a “real buzz” in the staff canteen, where he went from table to table to politely interrupt lunches. Observers noticed his eagerness to connect with people and he took genuine interest in their roles and dedication to the cause.
Introverts content with standing to one side in the corridor they almost doubled for portraits were unsuccessful. Ten Hag disarmed them with a “hello” or asked for their name and their occupation. One canteen staff member was recognised by McClaren from his first spell with United.
Ten Hag listened to opinions as he worked the floor and made some staff “feel like a million dollars”. He was generous with his time and, in an exchange with one staff member, marvelled at the away support he witnessed at Selhurst Park the previous day.