One man that stood out for his shocking performance was Anthony Martial.
The Frenchman has struggled for performances this season, surprising especially after the excellent season he had last season, even bagging a hat-trick against the Blades in the same fixture.
He looked like a shadow of himself yesterday, struggling to do the simple things right, misplacing plenty of passes throughout the whole game and failing to beat George Baldock and Chris Basham and get past them.
Martial might have had a goal wrongly disallowed and he might have got a knock early on, but it would have simply masked what was a truly disastrous showing from the 25-year-old.
Plenty of fans have been calling for Ole Gunnar Solskjaer to bench Anthony Martial since the start of the season, and the game against Sheffield United would have been the perfect game to let him sit out the game and get some rest, with Edinson Cavani being much more suited to the type of game that the Blades wanted United to play.
Solskjaer might have rested Cavani for the Arsenal game, but at the end of the day, it would have been better to play Martial in the Arsenal game rather than this game, being much better on the counter than when he is facing a deep backline.
What would be extremely worrying for Solskjaer is Martial's failure to track back and his lack of work-rate when he was shifted to the left-wing, highlighted by the second goal conceded, standing there not knowing what to do as Sheffield United made pass after pass right next to him.
Martial has managed just five goals and seven assists this season in 25 games in all competitions, which is extremely underwhelming considering that he had 23 goals and 12 assists in 48 games last season, when United were performing much worse as a whole.
Martial's best performances this season came against RB Leipzig in the UEFA Champions League, and against Leeds United and the reverse fixture against Sheffield United, but in all of them he was more dangerous as a creator, rather than a finisher, which could show his inconsistency in front of goal.
According to statistics from Whoscored, Martial's performances in the Premier League have dropped off massively since last season, from an average match rating of 7.31, to just 6.83.
However, Martial might have had a horrible game, but every United player should be blamed for the atrocious performance yesterday, and they will need to recover quickly, with a trip to in-form Arsenal coming up on Saturday.