If the Premier League season has felt like a constantly unfurling vindication of Pep Guardiola’s football philosophy and life's work then on a famous European night at Anfield, it was the turn of Jurgen Klopp.

The first half of an electrifying evening was the realisation of everything Klopp holds dear in football. Counter-pressing in full effect, winning the ball high up the pitch, claiming almost every second ball, cutting City’s defence apart with rapier-sharp attacks as they hurtled up the pitch again and again. It has been two-and-a-half years of inconsistency under Klopp, and some suspect defending has seen faith waver at times, but this is why he was brought to the club. This was Klopp at his Kloppiest.

transfers Liverpool in 'regular contact' with Mbappe over 2021 move - report YESTERDAY AT 20:29

The second goal was probably the purest example of Kloppian football: James Milner smacking into a challenge on Ilkay Gundogan seconds after Liverpool had lost possession, with the ball flying square to Alex Oxlade-Chamberlain, who thumped it past Ederson. Fast, vigorous and quick-witted. It was the perfect encapsulation of the “heavy metal” football that Klopp once claimed as his style, but has since distanced himself from. And if that goal was a glimpse of an underlying playing style coming to the surface, the totality of what transpired at Anfield also recalled one of Klopp’s other guiding principles: the romanticism, and potential, of the underdog.

In an interview in November 2013, ahead of a meeting between his Borussia Dortmund side and Arsenal in the Champions League, Klopp revealed an insight into his mentality. "The important thing is new ideas, not money," he said. "It is important to make the next step. You always want to be the team that can beat the one with more money."

Two years later, after deciding to take on the Liverpool job when he had been linked with clubs like Real Madrid, he touched on a similar theme in an interview with a young Reds supporter: “I love this game because you can win against better teams if you work better together than the other team. That’s what I really like. It’s why I love to be a manager and why I love this game.”

Mohamed Salah et les joueurs de Liverpool célèbrent un but face à Manchester City en 1/4 de finale aller de Ligue des champions Image credit: Getty Images

This strand of Klopp’s thinking was realised in glorious technicolour at Anfield. Against a City side with two full-backs and a goalkeeper who all cost more than Mohamed Salah, it was Liverpool winning every 50-50; Liverpool running themselves into the ground to halt City attacks from the outset and then launch their own; Liverpool players, like the magnificent Andy Robertson, haring the length of the pitch to strike fear into the most expensive squad ever assembled in the history of football. Money runs through Manchester City’s veins. The City Football Group is a project unrivalled in its ambition. And yet here they were, being utterly disassembled on their biggest night of the season so far.

If it was a night for Klopp to savour the purest expression of his ideals, what of Guardiola? The Premier League season has drummed to the beat of City’s percussive passing football. They have been almost untouchable, week after week, and could win the title ludicrously early on Saturday when they take on Manchester United. Watching Kevin De Bruyne display his full repertoire of passing has replaced church as the nation’s favourite weekend religious observance. And yet, this gloriously talented team now find themselves on the precipice of European disaster.

It has been an unfortunate theme of the second act of Guardiola’s career: almost a self-fulfilling prophecy. He won the Champions League twice at Barcelona to install himself as football’s foremost thinker but his European vistas have receded since: three semi-final defeats at Bayern Munich and now, barring a miraculous turnaround, a quarter-final and a last-16 defeat in two years at City.

The tie may yet be rescued, even if it will require a Herculean effort. But irrespective, questions will linger about Guardiola’s tactical decisions. Leaving out Raheem Sterling and clogging up the midfield by deploying Ilkay Gundogan alongside Fernandinho, De Bruyne and David Silva looked to be a major mistake. Gabriel Jesus malfunctioned up front and, even worse, the use of Aymeric Laporte as a left-back backfired badly.

Liverpool's Andrew Robertson in action with Manchester City's Aymeric Laporte Image credit: Reuters

Using the January signing in the same position in the weekend’s win over Everton looked like an audition for the Anfield job, but Theo Walcott is not Salah and Laporte was badly exposed while Fabian Delph and Oleksandr Zinchenko looked on from the sidelines. Guardiola’s brain is without peer in elite football but to the untrained eye these looked like unforced errors. Not for the first time.

"I got it wrong man. I got it totally wrong. It’s a monumental f***-up. A total mess. The biggest f***-up of my life as a coach.” Not the words of Guardiola last night, but on April 29, 2014, when his Bayern Munich team were eviscerated 4-0 by Real Madrid, at home, in the second leg of their Champions League semi-final. He let himself be talked into taking an excessively attacking approach by his players.

Two years later, the opposition were Barcelona in another Champions League semi-final. A headstrong Guardiola decided to match the most extravagant three-man attack of all time with a three-man defence going to man-to-man, which left Mehdi Benatia, Jerome Boateng and Rafinha left virtually alone to cope with Neymar, Luis Suarez and Lionel Messi respectively. Barca swarmed over the Germans, Bayern reacted after 15 minutes of chaos and returned to a back four, but went on to lose 3-0.

Guardiola barely put a foot wrong domestically with Bayern either. The Bundesliga was his playground where every idea was executed and every fevered tactical dream fulfilled. As the Premier League has been this season. But if there is no turnaround at the Etihad then questions will grow about his decision making when it really counts in Europe.

Whether it was the fault of the broken windows of the City bus, the fiery atmosphere inside Anfield or just a basic error on Guardiola’s part, City flunked this test spectacularly. Unless a similar miracle occurs, it will be a reinforced Klopp who goes through to the last four, in search of his second Champions League final since Guardiola last made one.

Premier League A good week's work for Klopp as Liverpool hit stride 20/09/2020 AT 18:43