It had been coming all season.
Manchester United have been flattering to deceive and, regardless of how much paper was applied to the cracks, it was inevitable that something was going to go wrong somewhere.
Of course, there was the comeback against Crystal Palace after falling two goals down and the defeat of Liverpool at the weekend in which Jose Mourinho's low risk football was rewarded with plaudits about his 'tactical mastery'.
But lying beneath the surface lingered the same doubt. Manchester United have failed to blow away sides in the sort of manner that you might expect a team sitting second in the Premier League to do at least a few times a season.
The season did, it must be admitted, beginning with a number of convincing results but, as time has slowly trundled on, so have Manchester United, culminating in yesterday's horror show which saw the Manchester-based side have four shots on target in 180 minutes against a team who have conceded 42 league goals this season and 12 in six Champions League group games.
After the game, the Portuguese manager pointed out that Manchester United have been the in same position before although, perhaps unwisely noting that he was the manager on two occasions.
For Manchester United fans, though, this is the end of the tether. You can talk up the importance of the table all you like but the startling regularity of disappointing performances, particularly in cup competitions, is unforgiveable for a team that should be producing better.
Steven N'Zonzi puts United midfield to shame
An utterly drab first 45 minutes ended goalless, emphasising just how badly Manchester United need a ball playing midfielder to complement the solid defensive base provided by the tall Serbian Nemanja Matic.
Former Mourinho golden boy Marouane Fellaini failed to influence the Champions League tie in the first-half and looks likely to depart Old Trafford in the summer after rejecting a new deal.
With Paul Pogba seemingly out of favour and starting on the bench alongside relative novice Scott McTominay, Mourinho must spend big on a player in the Paul Scholes/Michael Carrick mould - a ballplayer who can dictate the game's tempo.
The outspoken Portuguese manager has to look at the likes of Sergej Milinkovic-Savic, Jean Michel Seri and Toni Kroos in the summer if his team are to push Europe's best for the top prizes - that much was clear from a turgid first-half of football.
Sevilla's Steven N'Zonzi did the basics well, as he almost always does. The 29-year-old kept things tidily ticking over in the first-half, regularly winning the ball back for his side and exhibiting some impressive tackling to boot.
The man brought to England by Sam Allardyce for £400,000 in 2009 really has improved immeasurably since stints with Blackburn and Stoke. Premier League clubs in need of a solid midfield starter could do a lot worse than the two-time French international, and I include United in that statement.
Second-half United sloppiness leaves Mourinho with egg on his face
The Manchester United manager's inability to get a tune out of the wealth of attacking riches is a catastrophe given the amount money spent.
Take Alexis Sanchez, for example. He still hasn't settled into the Red Devils' attack, having been somewhat shoehorned in since his January move from Arsenal.
It's no secret that United have looked better with Marcus Rashford, Anthony Martial, Jesse Lingard and Romelu Lukaku as their main attackers this campaign. If Mourinho had any backbone he might have dropped the underperforming and infective Chilean, who offered little on the night.
A lethargic looking Paul Pogba replaced Fellaini in central midfield on 60 minutes but could do nothing to stop substitute Wissam Ben Yedder firing Vincenzo Montella's side deservedly ahead in the 75th minute, just 87 seconds after coming on.
Throughout the game, Manchester United's midfield was constantly overrun, making Mourinho's decision to play a 4-2-3-1 look positively mediaeval. The substitute Pogba, once the most expensive player in the world, looked poor.
You reap what you sow
You reap what you sow in the beautiful game: United conceded another just four minutes later to make it 2-0 to Sevilla, that man Yedder heading home from a corner render the rest Manchester United's season largely pointless.
It's no exaggeration to say the 26-year-old striker could have scored a hatful, such were the home team's defensive frailties.
A goal from Lukaku at least made the final few stages look competitive but Mourinho's scathing attack on Frank De Boer came back to bite him as the Portuguese manager's negative tactics ensured that Rashford was on the losing side, despite his best efforts.
As Steve McManaman aptly stated on BT Sport's live coverage: "United and Mourinho have had a shocker" - he's right.
Manchester United under Mourinho have fallen short of the pace set by Pep Guardiola's Manchester City in the Premier League, failed in the Champions League at the first real hurdle, crashed out in the League Cup to Bristol City, all of which leaves the FA Cup as Manchester United's only realistic shot at a trophy this season.
Barring a complete capitulation in the league Mourinho's men side should finish comfortably in the Champions League qualifying positions. However, the 2017/18 season has been one of steady decline as Mourinho's magic - and with it his mystique - has slowly petered out.
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