One of the many banners at a sentiment-soaked Old Trafford, red paint on a white sheet, said simply: "Sir Alex: Immortal." Football, and Manchester United in particular, does immortalise its legends, with statues, histories, the naming of stands, yet throughout this long, celebratory farewell, Sir Alex Ferguson looked very human, even a little vulnerable. There he was at the centre of this huge, red empire he worked that relentless 27 years to build: just one elderly man, in his overcoat, retiring for his wife after the death of her sister.
The speech he gave on the pitch at the end was unscripted and so not crafted by any spin doctor to perfectly frame the themes of this great modern football leave-taking. Instead, alone in front of 76,000 supporters waving Champions flags in the steepling stands, and the Premier League's millions watching around the world, he kept it simple, as, in some ways, he has throughout his time at the heart of United. He thanked the crowd, reminded them with humility that he might have been long, long gone had Mark Robins not scored the winner for United in an FA Cup tie at Nottingham Forest in 1990 when Ferguson was on the brink of the sack.
"When we had bad times, the club stood by me," he remembered, skipping the 13 league championships and two Champions Leagues he stayed on to win. Then, typically, he looked ahead: instructing the fans to stand by his successor, David Moyes, who must walk into all this and achieve just as much.
Where might United be now had Robins, now the Huddersfield Town manager, not grabbed that winner and the club decided to keep their newish Scots manager on? How many more short stints of United managers listed below Ferguson in the Sky Sports Football Yearbook, how many fewer championships won, how much less national and global dominance by United and the Premier League itself.
Instead, as millions of words have attested since the news of his retirement broke on Tuesday night, United kept him, and he stayed, not only to build great teams, but to have a new incarnation of a football club constructed all around him. His statue, round the other side of the ground from the forecourt over which Sir Matt Busby's bronze gazes benevolently, has him with arms folded, a more businesslike pose.
He stands above the entrance to United's money-spinning museum and tour centre and Red Cafe, and three expensive ways to watch football: in the Manchester Suite, Platinum Lounge and Salford Suites. Busby stands over the megastore, a slight irony, given that United took the souvenir shop back from him after he opposed the Edwards family's rights issue of 1978, an action which signalled the start of determined money-making by successive owners out of United.
It had sold out of programmes, and queues for the stalls in the rain outside stretched back 20 yards, for the souvenir copy, the one to keep and pass on to the grandkids, which said on the front: Thank you Sir Alex. That is what Manchester United FC – and Manchester United plc (Cayman Islands) – have been saying all week, simply that, with a hashtag in front of it for the 659 million Twitter followers they now claim to have.
It never was true, as the myth-making had it when Ferguson began building his dynasty, that all United fans were spread around the south, nor, as lifelong fans began to grumble, "day-trippers" from abroad. The 76,000 scurrying into Old Trafford looked as they always do, mostly Manchester stock, not greatly gentrified, although largely older than the regulars were when Ferguson arrived in the 1980s with a Stretford End ticket costing £3.
When a group of five lads in their late teens walked across the forecourt singing, they were an oddity, almost a breach of the peace. Inside, the megastore was heaving, with not just tourists rifling through replica shirts at £50 each this season. The "day-trippers", though, were the ones exiting with carrier bags, taking the opportunity to buy because they cannot be here week after week. Lee Brian, 27 from Hong Kong, was visiting his brother and paying this visit to the famous Manchester United. Asked if he was buying much, he laughed, pointed to a basket overflowing with kit and merchandise, and grinned: "Yes."
Mohamed Hassim and Rafique Omar had come from Johannesburg with their sons, specially for the game, £2,500 each for the trip. They started supporting in the 1980s when the South African Gary Bailey played for United in goal; then they nibbled on snippets in the newspapers, now they can watch every game live at home in South Africa.
In 1993 when Ferguson won for United the first championship of the Premier League breakaway era, this was all new, the superstore and the megastore, the merchandising, the very idea of building so huge a commercial operation from football support. The Independent Manchester United Supporters Association began their protests in shock at ticket prices which had reached £15, and the gradual sedating of the atmosphere.
On this day, it was loud, emotional, a constant, cascading chorus in flag-waving praise of Ferguson. It was all red, no green and gold, and not a hint of protest at the Glazer family, who sat as implacable as ever in the directors' box watching the scenes of thanksgiving at this English football temple they so improbably own.
They made a contrast with the Swansea City directors in the front row, all local men and lifelong fans, including the elected supporters trust director Huw Cooze, who all jumped up, hugged and backslapped each other, when Michu scored his deftly volleyed equaliser.
There was only so much emotion to go round, and the crowd had to dip into their reserves to see Paul Scholes on his way off to his retirement, then welcome Ryan Giggs on, the local boys who grew up into greatness under the nurture of Ferguson.
Truly, an era ended here, the departure of this one man who extraordinarily endured and phenomenally succeeded, spanning that time of terraces and trouble, to choreographed triumph. Rio Ferdinand lashing in the winner might have been scripted, to finish with a win, late on, the day the latest and last trophy was presented.
The question is just beginning to be faced, beginning with Ferguson's warning to the crowd: where will it go from here? He has said he is leaving "the organisation" – the team, the youth production line, the stadium, the training facilities – in the best possible shape for David Moyes, but there is huge expectation, and a gap to bridge to European success.
Ed Woodward, who has squeezed the global sponsorships for the Glazers, steps up to replace David Gill as the chief executive, and it remains to be seen if the club will provide a level of investment beyond that with which Ferguson has worked wonders in the most recent, debt-laden years.
Football is a grand and surprising storyteller, and anything can happen next. Moyes, and Woodward, have a daunting task, to come in after a history-making era of total transformation. But full, loud, a flag-waving red empire, there felt something impregnable about what has been built here, in all that Fergie time.