Brennan Johnson, Dejan Kulusevski and Dominic Solanke scored the goals as Tottenham Hotspur took apart a Manchester United side who also had Bruno Fernandes sent off.
After reportedly narrowly escaping the sack in the summer, Erik ten Hag may well be fearing for his job after a weak performance.
From the off, Spurs were first to every ball, and it was no surprise when they took the lead on three minutes, Johnson tapping home at the far post after fantastic work from Micky van de Ven.
Though Spurs didn't score again in the first half, they absolutely dominated as United shrunk. Then, with three minutes until the break, Fernandes slipped as James Maddison passed him, lunged, and was sent off after his challenge landed higher than intended.
Handed an opportunity to reorganise, Ten Hag will have been dismayed to concede within two minutes of the restart, Kulusevski finishing cleverly after more good work from Johnson.
Then, just as United established a foothold in the game, Spurs made it safe, Solanke sliding in after Pape Sarr flicked on a corner.
In the time remaining, the away end mocked the home fans, team and manager - a state of affairs that sees Ten Hag under yet more pressure.