The uncomfortable truth David Moyes faces after this reverse is that here was a display as concerning as last Sunday's derby humiliation at Manchester City.
West Bromwich Albion cruised through this in a manner that the champions of England should not countenance on their own turf. By the close a repeat of the 4-1 scoreline at the Etihad Stadium could have happened against a United side that missed key performers and will cause question of Moyes's selection.
Steve Clarke's men were not as stellar as City had been but though United rallied towards the end the sense was of a display almost as insipid as they turned in during that 166th edition of the local squabble.
This had the joyous travelling support singing, "We'll sack who we want, we are the Albion, we'll sack who we want," as they took over Old Trafford for the afternoon.
The contest featured the two finest goals seen here this season. One was a supreme individual effort, the other a collective offering also converted by a superb finish.
Both were scored by West Brom. First, Morgan Amalfitano took possession and proceeded to skate at Rio Ferdinand, nut-megging the veteran defender before dancing towards David De Gea and dinking a sublime chip over the keeper.
This was on 54 minutes. Within seconds United were level. Perhaps being unhappy suits Wayne Rooney, because the forward who has started the campaign like a juggernaut, collected a fifth goal in six games when his free-kick came bending from the left and missed everyone, including the visiting keeper, Boaz Myhill, and that was 1-1.
This was not the end of the West Brom challenge, though. Amalfitano nearly added a second with a zinger of a free-kick that De Gea tipped over superbly. But then, the Frenchman contributed to Saido Berahino's strike with a pivotal touch from Stéphane Sessègnon's pass, the ball falling into the Burundi man's path for him to let fly with a bullet that gave De Gea no chance.
Ahead of what had been a first chance to return a league win following the derby reverse Moyes described the mood at the club as "embarrassed" following that performance.
He may feel the same now.
OTHER RESULTS
OTHER RESULTS
FT | Tottenham Hotspur | Chelsea |
FT | Aston Villa | Manchester City |
FT | Fulham | Cardiff City |
FT | Hull City | West Ham United |
FT | Manchester United | West Bromwich Albion |
FT | Southampton | Crystal Palace |
Aston Villa beats Manchester City 2=0