The fatal goal in Sunday's debacle was scored by Manchester United themselves. There was an authority to Darren Fletcher's drive that cut the deficit to 3-1, and the minds of team, support and manager must have started to swim with thoughts of one more uncanny recovery in the club's history.
At that moment, it did not seem to matter that the lineup had been reduced to 10 men by the red card for Jonny Evans, yet the true consequence of boldness turned out to be the 6-1 rout by Manchester City. For once, events were beyond the reach of Sir Alex Ferguson.
In a peculiar aftermath it was the overlord of Old Trafford who spoke as if he had been a passive onlooker. Ferguson suggested that his side should have adopted a conservative approach and aimed for a humdrum defeat. Given the three goals scored from the 90th minute onwards, there was sense to that proposal. The manager, however, had inadvertently raised another issue.
Any fan was entitled to ask why the side did not do Ferguson's bidding. Perhaps he and his players were in shock long before stoppage time. United, after all, had been in reasonably good form and the talk following matches with lesser teams was often of regeneration.
Arsenal, collapsing in an 8-2 debacle, were completely unaware of weakness. It takes performers such as City's David Silva, with that combination of vision and execution, to cow the Premier League champions. Even so, United had already been conscious of difficulties in their midst.
Only once has Ferguson been able to send out the same back four in consecutive games, against Tottenham Hotspur and then Arsenal. While the club have a heritage of breezy football, the spontaneity has been getting out of hand. United have allowed the opposition more shots on goal than any other club in the Premier League this season.
The defensive midfielders were overrun by City. That was perhaps natural with United undermanned, but there have been countless occasions in football when a 10-man lineup regroups to become more and more resolute.
Indeed, United are precisely the sort of side who can generally be counted on for obstinacy. Ferguson would have been ridiculed if he had pleaded mitigating circumstances because a club of such renown are meant to be equipped for every type of adversity.
Even so, there are insidious factors. Continuity has been elusive, with the preferred centre-halves, Rio Ferdinand and Nemanja Vidic, together in the Premier League for only 52 minutes, in the win at West Bromwich on the opening weekend.
It is obvious, too, that the emergence of Ferdinand from the tunnel does not end the discussion about his value now or in the near future. Fabio Capello can be relied on for brusqueness. "He has not played enough and last week he was on the bench," said the England manager after omitting the defender for the squad for the Euro 2012 qualifier in Montenegro.
At club level, where alternatives are limited, it is not feasible to be so high-handed. There has to be an assumption that Ferguson had qualms about Phil Jones, even if he did cost some £18m from Blackburn Rovers. No one seems sure he is ready yet to be a top-level centre-half.
The teenager was employed by England on the flank during the 2-2 draw with Montenegro in Podgorica so that he could make powerful runs. Ferguson let him on to the field against City when there were only 24 minutes remaining.
The United manager has been so adroit at constructing teams that the degree of difficulty in the project goes unrecognised. It is fair to salute Roberto Mancini, the Manchester City manager, for the development of his side's style, but he operates in a financial environment that barely exists elsewhere, unless Roman Abramovich is in the mood to persist with the spree at Chelsea.
United themselves have moments of extravagance, but there is also an old-fashioned trait that sees them profit by, for instance, selling Cristiano Ronaldo for £80m in 2009. Disgruntled as fans were, there was also an appreciation that the attacker was set on joining Real Madrid.
The paucity of the showing on Sunday is not to be ignored, but Ferguson's approach will rest, first of all, on making more out of what he already has. United are far from poor, but the real riches of Old Trafford lie in the manager's talent.