It will, as ever, be a clash of contrasts. The joy machine against the tortured genius. Extrovert versus introvert. Low-slung baseball cap versus designer knitwear, ordered chaos versus chaotic order, 4-3-3 versus who-the-hell-knows, blood red versus cool blue, the hair transplant against the immaculate bald pate. For the past eight years, this is the duel that has painted the skies of English football, took it to new and unfamiliar places.

And now, the end. For all the antagonism Liverpool and Manchester City fans have developed for each other over the years, Jürgen Klopp and Pep Guardiola could never truly bring themselves to hate each other. The mutual admiration and grudging respect simply ran too deep. “The outstanding manager of my lifetime,” as Klopp put it this past week. “The best rival I ever had in my life,” according to Guardiola.

It wasn’t meant to be this way, of course. When Guardiola arrived at City in 2016 the prevailing narrative was one of renewed hostilities with José Mourinho, unveiled at Manchester United in the same summer. An ailing Liverpool had finished eighth the previous season, with Klopp taking over from Brendan Rodgers in October. English football’s newest toxic rivalry did not, essentially, exist yet. For Guardiola, Klopp, Mourinho, Antonio Conte and others, building a breathtaking dynasty would have to take a back seat. First task: knock Leicester off their perch.

Perhaps in retrospect we should have seen what was coming, given the way Guardiola’s Bayern Munich and Klopp’s Borussia Dortmund had so thrillingly tussled over their three seasons together in Germany, given the evident polarity in their two philosophies, dominance of the ball versus dominance of space. But  this was a slow-burn of a rivalry, one that did not really take shape until the first half of 2018, when City’s immaculate champions-in-waiting were beaten 4-3 at Anfield in January before being blown away 3-0 in a Champions League quarter-final first leg.

This was perhaps the point of maximum divergence: the brilliant waifs and sprites of City, with their mesmeric and cultured short passing game, coming up against the tearing gale of Liverpool, with its speed and aggression and a Scottish left-back bought from Hull. Over the subsequent years, Guardiola and Klopp would increasingly develop around each other like winding vines, constantly anticipating and reacting, borrowing and stealing.

For Guardiola countering the Liverpool counter, staunching that lightning front three, would become an obsession that defined his later teams. It led him to resurrect an idea that had been pioneered by Johan Cruyff, of pushing his full-backs into midfield when his team were in possession. Later this idea would evolve even further, culminating in the deployment of John Stones and Manuel Akanji in a kind of defensive-midfield hybrid role last season. “His teams helped me to be a better manager,” Guardiola said. “It is the reason why I am still in this business. There are some managers who challenge you to move a step forward.”

For Klopp, the stratospheric standards set by Guardiola’s City persuaded him that his Liverpool team would need to rein in their anarchic side in order to challenge for the title, to develop better and more reliable ways of recycling the ball against deep-set defences. Training exercises were increasingly geared towards structured attacking patterns, repeatable movements, drilled actions such as two men making dummy runs in the same direction so a third could exploit the space they created. Liverpool’s average possession rose from 55% to 63% in Klopp’s first five seasons, culminating in his restrained masterpiece: the title-winning season of 2019-20, in which 15 of their victories came by a single goal.

So there was a kind of symbiosis at work here, a shadow war that was most evident in their games against each other. Sometimes they cancelled each other out; at other times their fear of each other led them down weird tactical cul-de-sacs. The deployment of Jack Grealish as a false No 9 – a role he had never played before for City – in a 1-1 draw at Anfield in October 2021. The decision to play João Cancelo and Phil Foden as wing-backs a year later, a decision that backfired with a 1-0 defeat. Last April, Klopp went for all-out attack at the Etihad Stadium against a City missing Erling Haaland, and his side were devoured in midfield in a 4-1 defeat.

England, naturally, would provide the perfect canvas for this dialectic: a goldfish bowl of theatre and outsized melodrama and screeching crowds and feverish devotion, but also a footballing culture crying out for a certain refinement. Quite apart from the success each has enjoyed – the four highest points totals in Premier League history, an appearance in five of the past six Champions League finals, the Big Six briefly rendered a Big Two – what is most notable about this era is the way they have consecrated principles that were at best contested when they arrived.

Everybody now presses high. Everybody now recognises the best time to win the ball back is when you’ve just lost it. Even amateur teams now pass the ball out from the goalkeeper. The result has been a certain homogenisation of style, the development of a footballing monoculture. But it is hardly the fault of Klopp and Guardiola that they were so good everybody felt the need to copy them.

With all the appropriate allowances for recency bias, the past eight years really do feel like a kind of golden age. What the Lionel Messi/Cristiano Ronaldo duopoly was to La Liga in the 2010s, Guardiola and Klopp have been to the Premier League: excellence begetting excellence, a shining exemplar that cast everything around it into a kind of irrelevance.

For any coach worth their corn, the Premier League became the place where you needed to prove yourself. Great coaches – Carlo Ancelotti at Everton, Manuel Pellegrini at West Ham, Mourinho and Conte at Tottenham – took jobs beneath their standing in a desperate attempt to cling on to this world, to be where life was. Will this still be the case in five years, after Guardiola goes, after Liverpool have rebuilt, after the court cases and the realignments?

Guardiola stays, for now, but he, too, is nearer the end than the beginning. Perhaps these two will meet again, either in the FA Cup or in some other league, or perhaps even in international football one day. But to all intents, once the final whistle blows on Sunday afternoon, all this will pass into memory. The curtain is coming down, and not just on a coach, or a rivalry, but what feels like a whole era of English football.