Bad results can happen at any time.
Even absolute hammerings can come around when you least expect it, even if they're becoming alarmingly regular for Manchester United, but a loss of such magnitude is a rare thing.
It's not even just the fact that United lost 5-0, that they lost 5-0 at home, that they lost 5-0 at home to their greatest rivals, that they lost 5-0 at home to their greatest rivals to already go eight points behind in the Premier League title race.
It was the manner in which they did so. How they were so unorganised, how there was no clear plan, how full-backs, centre-backs, midfielders, wingers and a striker all seemed to act in complete isolation. How this isn't the first time and, should Ole Gunnar Solskjaer remain at the helm, it almost certainly won't be the last.
If you watch a well-coached side, in which everyone knows their roles and patterns of play are well drilled, it should look as if everyone is tied together by an invisible rope. If one player moves to the left, everyone shifts that way. If one player pushes forward, everyone else does in unison.
Instead of being anchored together, United are an armada that has become unmoored. Lost at sea.
Just look at the first goal Liverpool scored within the first five minutes of the game, the time in which the players theoretically should still have their managers instructions ringing in their ears, be at their most organised.
Mason Greenwood has come in from the right flank to press Virgil van Dijk as Cristiano Ronaldo isn't in the middle to do so. Then Aaron Wan-Bissaka has raced well ahead of his fellow defenders, into the opposition half, to close down left-back Andy Robertson. As he's gone forward, Victor Lindelof has had to go right to cover for him, then Harry Maguire has had to rush forward to close down Roberto Firmino, opening a gaping hole which Luke Shaw has had to come into to try and close down Mohamed Salah, which has left Naby Keita all on his own to slot home with ease.
Around 10 seconds of play in which six players were pulled out of position because of a lack of organisation and orders to work a press they cannot do. It's because of bad coaching.
Instead of moving as one, every player was having to react to the last player's mistake which just left them at the mercy of Liverpool. It happened time and time again. Jurgen Klopp's side wasn't even close to their best but won at a canter and if they hadn't have taken pity, shown respect or conserved energy - whatever your reasoning - it could legitimately have been double figures.
United finished second last season. But the gap between themselves and Manchester City was 12 points. It's likely that gap will be even larger this season.
Both clubs, it could be argued, have equally good squads and have spent ridiculous money on acquiring them, there is no reason in that regard why United can't be competing with their neighbours. The only difference is in the quality of the coach.
Pep Guardiola is an elite manager who has his team drilled to the most minute detail. Sometimes they might lose. Sometimes Guardiola might even get his tactics wrong, as he did in the Champions League final, but even when it's wrong the team still actually knows what it's doing.
Likewise, with Liverpool and Chelsea. Some teams aren't on United's level financially - Leicester City, West Ham, Brighton, Brentford, the list goes on - but their teams are coached better. A plan is clear to see in every game they play. That could even be applied to Burnley.
If he holds on for two more weeks when City visit Old Trafford, those differences may well be on show for all to see once again.
It can't be denied that Solskjaer was the right man when he was hired. He was the ray of sunshine to dismiss Jose Mourinho's dark clouds. He has made the team younger and more exciting to watch, there is more than enough quality in the squad to be serious title challengers - but it's looking ever more likely it won't be with him in charge.
But that's not his fault. He has tried his best. He has given absolutely everything. United fans know that and he will never lose his place in their hearts.
But the fact he remains in his position, when the same problems have been repeating themselves over and over again for three years, does show the ineptitude of those in charge. Or, that a United manager's job only becomes at risk when Champions League qualification - and all the money that comes with it - is looking in peril.
That key difference between City and United on the pitch points to the bigger differences of it: the aptitude of those in charge.
City hired Guardiola, but before they did that they made the club the perfect environment for him to flourish in. His friends and confidants - but more importantly people highly skilled at their jobs who had worked with him at Barcelona - were hired in key positions and every decision that they make - be it youth development, signings and everything else in between - are always aligned with the same philosophy.
They may not always be right, but they're always batting in the right direction at least.
Who makes the decisions at United? Solskjaer? Ed Woodward? John Murtough? Darren Fletcher? The Glazers? What direction are they pulling in? What's the structure? What's the identity? What are Manchester United and what are they doing?
The difference between the two clubs are just as stark off the pitch as they are on it but, whether he deserves it or not, Solskjaer is the man in the firing line.
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