Diego Maradona thrust his "Hand Of God" into the air and smiled in approval. If there was a moment that confirmed Liverpool's right to be taken seriously as Premier League title contenders, this was it.
The legendary Argentina World Cup winner, sharp suited and sporting deafeningly loud ear-rings, was in attendance in Old Trafford's directors' box on a day of huge and contrasting significance for Manchester United and Liverpool.
And Maradona, looking like a well-dressed pirate, will have savoured the quality in Liverpool's display on a day when the secret was well and truly out. Manager Brendan Rodgers, in the shadow of Chelsea and Manchester City, has shaped a side that can win their first title since 1990.
Maradona will have appreciated the movement and menace of his fellow South American Luis Suarez, whose partnership with Daniel Sturridge shone a harsh light on the seemingly dysfunctional footballing relationship between Wayne Rooney and Robin van Persie.
The Argentine will have noted the relentless work-rate and pressing of Jordan Henderson. He will have relished the enduring brilliance of Liverpool captain Steven Gerrard, now in a deeper role but still the controller.
If Liverpool needed to deliver a defining mission statement that they can stand alongside any of the challengers for the Premier League title on their own terms, they produced it most emphatically to humiliate Manchester United in their own self-styled "Theatre Of Dreams".
This was more like the stuff of nightmares for United manager David Moyes, who was worryingly at a loss to explain a shameful effort from the reigning champions that at times bordered on surrender.
Liverpool's domination was on such a scale that the sight of veteran defender Rio Ferdinand replacing £37.5m Juan Mata with three minutes to go as United trailed 3-0 was almost embarrassing. This was not so much a substitution as a plea for leniency.
Forget 3-0. This game was not as close as the scoreline suggests.
At this same stage last season, Liverpool stood on 42 points while United were heading for the title on 71 points. In the entire Premier League era, Liverpool had never gone into the second league meeting of the season ahead of United.
When Manchester United beat Liverpool 2-1 at Old Trafford in January last year it gave them a 24-point advantage over Liverpool who, in title terms, were a complete irrelevance.
It is an illustration of the turnaround, and of the wonderful work undertaken by Rodgers, that Liverpool now stand 14 points clear of United.
Former Liverpool manager Gerard Houllier once announced, mistakenly as it turned out, that his team were "10 games from greatness". This current vintage are nine games from the Premier League title and have that most precious of commodities to help them on their way. Momentum.
And, best of all for Rodgers, they have their destiny in their own hands with Chelsea and Manchester City to visit Anfield - where teams of the calibre of Arsenal and Everton have been taken to the cleaners this season. Some regarded this visit to United as their toughest remaining test but to say they passed it with ease is to do Liverpool a disservice.
While United's decline under Moyes has been sharp and startling, it would be wrong to suggest this played the major part in Liverpool's success at Old Trafford. This was the work of Rodgers and players he has filled with belief and freedom of expression.
As Moyes has struggled to coax anything out of United - how can a team containing Rooney, Van Persie, Mata and Adnan Januzaj be so utterly bereft of threat? - Liverpool are responding to Rodgers's methods with such gusto that it could now give them the game's greatest domestic prize.
Liverpool's 4-1 win at United under Rafael Benitez in March 2009 is regarded as a benchmark performance in the recent era. This was better, more convincing.
In that game, United led and the scoreline was given a slightly misleading appearance as Liverpool scored twice after Nemanja Vidic, as he was here, was sent off. Liverpool deserved to win but the margin flattered them.
Here, the 3-0 scoreline flattered United. Gerrard scored two penalties and missed another while United goalkeeper David de Gea saved magnificently from Suarez before he scored the third.
Liverpool have been picking up speed and confidence throughout the season to reach the point where they dominated United from start to finish. The home fans fell silent ominously quickly before a late show of defiance in the face of taunts from exultant Liverpool supporters.
Rodgers also showed his tactical acumen, leaving out Philippe Coutinho and using Raheem Sterling as the cutting edge of a diamond formation while utilising Joe Allen to help keep possession.
Liverpool have flexibility and threat. They currently look the most dangerous attacking team in the Premier League, with the power to score far more than an occasionally vulnerable defence will concede.
Manchester City and Chelsea may not relish those visits to Anfield, particularly with the Kop now sensing that long wait to take the title back to their home could soon be over.
Whether Liverpool win the title or not, Rodgers has done a remarkable job in restoring them to such status inside two seasons. The return to the Champions League, regarded as perhaps the height of achievement before the season started, now looks a formality. Sights are being trained on higher things.
In his recent autobiography, Sir Alex Ferguson, face seemingly set in concrete as he suffered with United's supporters on Sunday, could not resist a swipe at Liverpool as he wrote: "My reading of their squad was that they needed eight players to come up to title-winning standard."
If you are feeling particularly brave, you could suggest to the old streetfighter that on this desperate evidence it is United who require those eight players to even dream about title number 21.
No such concerns for Liverpool. They gained another illustrious admirer in Maradona as he looked on with pleasure.
Rodgers was coy while Gerrard was bullish but there is no hiding place for Liverpool any more - they can win the title and this was the performance of a team that believes it will.