It is 141 days since they last met in a match which confirmed how far Liverpool had risen and how completely Manchester United had fallen: a 3-0 defeat for the home team at Old Trafford in which their then manager, David Moyes, did not even consider his own side to be the favourites.
Both have covered some distance in so many ways ahead of their meeting in Miami on Monday night, in the final of the invitation International Champions Cup.
United, not Liverpool, will be the ones on the outside of European competition looking in now, but the 3-1 victory over Real Madrid on Saturday affirmed the sense that the intensity of their new manager Louis van Gaal's preparation and his attention to detail are paying a dividend.
"We can feel it coming back," said the midfielder Darren Fletcher. It is early days, but the side are more organised. They are displaying flashes of the quick inter-passing which Van Gaal wants from them. And they burn with an intensity which the Dutch former schoolteacher has already instilled in them.
Wayne Rooney looked nervous after Van Gaal had selected him to appear beside him in Friday's press conference; almost uncertain what to say. Van Gaal scrutinised him closely as he spoke; looking, as he has been this past fortnight, for many types of intelligence in his players. It was a revealing cameo, shedding more light on how United's players are on edge, in a healthy way.
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The Liverpool manager Brendan Rodgers' own search for intelligence is one of the many characteristics he shares with the Dutchman. A fast-moving brand of pressing and possession football, plus a relentless quest to understand his players and their lives, are two more. Rodgers, like Van Gaal, is three wins to the good in the United States and discovering grounds for optimism after the 2-0 win over Milan in Charlotte on Saturday. But after a far more frenetic summer in the transfer market than United, following Luis Suarez's departure, Rodgers has the more complicated task in knitting together the arrivals in a way which prevents Liverpool experiencing the problems which beset Tottenham when a Gareth Bale-sized hole materialised last August.
Adam Lallana, Rickie Lambert and Dejan Lovren achieved great things for Southampton but the expectations are far higher at Liverpool, who have a title to compete for. The problems Jose Enrique encountered against Manchester City's Stevan Jovetic last week served only to underline that the club need full-backs and there is confidence that Alberto Moreno will be signed from Sevilla.
But finding someone for the Suarez No 7 jersey is the monumental task. Daniel Sturridge and Lambert cannot lead the line alone. For all the difficulties Suarez caused, Rodgers could have done with him staying for one more season, helping the club that stood by him so stubbornly ease their way into the rigours of balancing European and domestic football.
In some respects, Liverpool's race to fit the pieces together makes Van Gaal's task look more straightforward. He needs a centre-half, with the attraction of Arsenal's captain, Thomas Vermaelen, being that he is one of the few ball-playing defenders of his type on the market.
Michael Carrick's remaining eight-week absence also makes a midfielder feel like a requirement, though Van Gaal's mantra about the system being more important than the players has made the search for new signings seem less panicked. Angel di Maria and Daley Blind are both targets, though the collective overrides individualism so completely with the meticulously prepared Van Gaal that he feels he could play the kit man if he showed the aptitude.
Fletcher's performances on tour have delivered Van Gaal an asset Moyes could never really call on. Fletcher's fight against bowel disease has deprived him of a pre-season for the past three years. The answers he and Rodgers have given to the question of what this season's target might be are revealing. A trophy, said Rodgers, still unable to expect a championship. A title, said Fletcher, echoing Rooney's declaration of last week: "We go out to win the league. It is a dangerous mindset to target fourth place. We are not players or a club that thinks like that."
The two old foes who meet in Miami are both finding their way and both likely to be one striker down. Sturridge has flown home after suffering a minor hamstring injury; Danny Welbeck was being assessed for a knee injury today. Yet, as always, the fixture reaches beyond the realms of analysis to something more visceral.
"It's Man Utd v Liverpool," Fletcher reflected. "I know it's only pre-season and it's just a summer competition, but when United play Liverpool, it is always a big deal."
Reborn in the USA? Pre-season successes and strugglers
Three winners from the Manchester United tour
Ashley Young Louis van Gaal has taken to his versatility by deploying him as a left and right-wing back. Four goals on tour.
Jonny Evans Most comfortable of all in the new three-man defence. Possible future captain.
Juan Mata Van Gaal's No 10 of choice and finally rediscovering the belief Rafa Benitez developed in him at Chelsea.
Javier Hernandez Has fallen behind Wilfried Zaha in the pecking order.
Tom Cleverley Seems like a typical Van Gaal technician but has been unable to seize opportunities on tour.
Luis Nani Struggling to make a meaningful impression. United willing to sell
Three winners from the Liverpool tour
Raheem Sterling His display against Manchester City underlined his readiness to take another big step. Has done enough to take Luis Suarez's No 7 jersey.
Jordan Henderson Particularly good against City but generally comfortable on the ball and driving into opposition boxes.
Jordan Ibe A young talent of great potential who dazzled against Milan.
Jose Enrique Cut apart by City's Stevan Jovetic in a display which revealed why Rodgers seeks new defenders.
Martin Kelly Has struggled for form on the tour and not looked confident. He appears to have been affected by injuries.
Glen Johnson Has shown more of the unpredictable form which has made him such a frustration.