When Liverpool stroll into the Tottenham Hotspur Stadium in the late afternoon, they might wonder what exactly it is they are walking into. 

Once, it would have been a battle between top-four hopefuls. Jose Mourinho vs Jurgen Klopp - a clash of true titans. 

As for the stadium itself? It will be Liverpool's first visit to the magnificent, 62,303-seater spectacle nestled into the Tottenham High Road. 

It was a building meant to signify a new dawn. Instead, since its opening in April - and with the exception of an obvious high in reaching the Champions League final - everything has fallen apart. 

Curious, that may be, for Liverpool, who just a couple of years ago found themselves with the same kind of seemingly interminable headaches.

A hapless defence. Goalkeeping issues. An over-reliance on one star player in the form of Philippe Coutinho. 

There was a recent time when these two giants of the English game were going toe-to-toe and one had just pushed Chelsea very close for the title in the previous season. It wasn't Liverpool. 

In October 2017, Spurs artfully picked the Reds apart in one of the first signs that the Wembley hoodoo would be banished. 

Mauricio Pochettino's men ran out 4-1 winners on the day, racing into a two-goal lead after just 12 minutes with goals from Harry Kane and Son Heung-min. 

Dejan Lovren's performance was so hapless it forced Klopp to withdraw the beleaguered Croatian after half an hour. 

But when we speak of 'Mauricio Pochettino's men', who are they? Well, almost man-for-man, the exact same players that will kick off at 17.30 this evening. 

As for Liverpool, there are resemblances, of course, between their current first team and the XI that was thrashed at the national stadium. They lined up as follows:

Tottenham: Lloris, Alderweireld, Sanchez, Vertonghen, Trippier, Eriksen (Dier), Winks, Aurier, Kane (Llorente), Son (Sissoko)

Liverpool: Mignolet, Gomez, Matip, Lovren (Oxlade-Chamberlain), Moreno, Milner, Henderson, Can (Grujic), Salah, Firmino (Sturridge), Coutinho

What's happened since is not one of the Premier League's great stories of haves vs have-nots, but one of neglect and underinvestment pitted against utter determination. 

Kieran Trippier has departed for Atletico Madrid and Fernando Llorente, who was only ever a bit-part striker, is now at Napoli. 

Liverpool, on the other hand, have undergone a transformation. Their goalkeeping options are now Alisson Becker, quite possibly the world's finest, with the more than capable Adrian as a back-up (Loris Karius was on the bench that day). 

Trent Alexander-Arnold and Andy Robertson have transformed the very definition of a full-back, never mind what they have done for the champions-elect's back four. Alberto Moreno is thankfully a distant memory. 

Lovren has slipped down the pecking order, his catalogue of errors convincing FSG that £75m was actually a small price to pay for Virgil van Dijk. Incidentally, a deal for the Dutchman was completed just two months after this result. 

Sadio Mane was on the books, though he didn't play that day. The fact remains that without Coutinho - a sale which could have decimated Klopp's attack - they have gone from strength to strength. A certain predictability has gone as they have moved towards a more potent, out-and-out forward three. 

In the midfield too, Gini Wijnaldum and Naby Keita have come in to establish themselves, with James Milner ever dependable but at 34, playing fewer games. 

Did a then Premier League record crowd of 80,827 realise they were watching a sliding doors moment? How many of them would have believed a messenger from the future, bearing news of a Liverpool team 13 points clear at the top of the table in January, unbeaten and having dropped points in one game all season? 

Tottenham's demise has not necessarily been wilful.

Daniel Levy is a boyhood fan who wants his club to succeed and is, by all accounts, aware of what it would have taken to make that final step which was in touching distance in 2017. The one or two major signings which would have certified with a Premier League title what most suspected about Tottenham being the best team in the country for a good 18 months. 

The suspicion, remains, however, that this is a chairman unwilling to commit the resources which are badly needed in terms of transfer fees and wages for the current squad. 

Mourinho's appointment was supposed to paper over those cracks, a quick-fix £15m-a-year strategy to avoid what would now likely be a £200m project. The "painful rebuild" of which Pochettino warned. A right-back, a left-back, probably two central midfielders, a central defender, a back-up striker, and in the long run probably a new goalkeeper too. 

Liverpool do not have a shiny new stadium. Accordingly, they also do not find themselves in the midst of an identity crisis.

They have an expensively-assembled squad, but one which is built on foundations of rich history and tradition. Perhaps Levy might dwell on that should the worst happen this evening.