A rupture occurred in the shadow of Mount Vesuvius. It was Liverpool, ripped apart and destroyed by Napoli on a humiliating night when Jürgen Klopp’s team resembled Champions League novices not seasoned finalists from three of the past five years.

The worst European performance of Klopp’s near seven-year reign – it is hard to think of another that comes close to the unwanted accolade – produced one of Liverpool’s heaviest European defeats. And a rare, necessary apology from Klopp to the travelling fans afterwards.

Liverpool were torn open from the outset and unrecognisable in every facet of a Klopp team, leaving the manager to admit: “We need to reinvent ourselves.” The rupture will extend from the performance to the fall-out.

Klopp stated beforehand that he wanted Liverpool to extinguish the emotion and aggression that Napoli feed off inside their stadium through football principles and compact defending. His players never read the memo. They poured oil on the incendiary atmosphere inside Stadio Diego Armando Maradona instead with a passive, chaotic performance in which their defence was shredded time and again. By the time Andre-Frank Zambo Anguissa scored Napoli’s second in the 31st minute it could easily have been 5-0 to Luciano Spalletti’s vibrant side. They had missed a penalty, hit a post and had a shot cleared off the line. The hosts sliced through at will in the first half especially. Liverpool, abysmal from back to front, offered little resistance and were flattered by a 4-1 defeat.

The Liverpool manager’s instructions were abandoned after 42 seconds. Amir Rrahmani and Stanislav Lobotka brought the ball out of defence with casual ease before Giovanni Di Lorenzo sent Victor Osimhen racing into a 50-50 with Alisson. The pacy striker got there first but swept a shot from a tight angle against the base of a post. Napoli had revealed their hand to play quick, incisive passes behind the Liverpool defence. The visitors paid no attention.

Osimhen had almost been played through again before the home side took a deserved fifth minute lead from the penalty spot. Khvicha Kvaratskhelia, or Kvaradona as the Georgian has been christened following his explosive start to life in Naples, teed up Piotr Zielinski for a shot that deflected just wide of Alisson’s goal. It was deflected via the outstretched hand of James Milner, Liverpool’s captain for the night, and Zielinski sent Alisson the wrong way from the resulting, clear penalty. Milner soon went into the book for a heavy lunge on Zambo Anguissa.

Napoli were awarded a second penalty when VAR advised Spanish referee Carlos Del Cerro Grande to revisit a challenge by Virgil van Dijk on Osimhen. Play had continued after the striker’s attempt to turn inside the Liverpool defender but, on his pitch-side monitor, the referee spotted contact between Van Dijk and Osimhen’s right foot. Osimhen, not Zielinski, took the second spot kick and in the same direction as the first. Alisson sprung to his right to make a fine save and Di Lorenzo skied a gilt-edged chance from the rebound.

While Del Cerro Grande consulted his monitor Klopp railed at Fabinho and his defenders for their shambolic opening. Yet it got worse after the penalty miss. Kvaratskhelia embarrassed Fabinho by turning him three times in the same move inside the centre circle. Osimhen dispossessed the dawdling Joe Gomez to advance into the penalty area where Kvaratskhelia stood unmarked. The pass to the 21-year-old was delayed and poor, however, giving Van Dijk opportunity to clear his eventual shot off the line.

It was soon two when Gomez was dispossessed again, this time by Kvaratskhelia. Zambo Anguissa exchanged passes with Zielinski and strolled into the area without meeting a challenge before beating Alisson with a cool finish. It was his first Napoli goal but not the end of Liverpool’s torment. As bad as Klopp’s team were, and their problems were not confined to defence with Mohamed Salah struggling to control the most routine of passes, they created enough openings to have doused Napoli’s mood. Goalkeeper Alex Meret tipped over from a Trent Alexander-Arnold free-kick and saved well from a van Dijk header. Salah and Harvey Elliott also missed decent chances.

Liverpool appeared to have been granted relief when Osimhen limped off injured before the break only for his replacement, Giovanni Simeone, to score Napoli’s third with one of his first touches. Gomez’s dreadful night continued when he was out-manoeuvred and out-fought by the superb Kvaratskhelia near the by-line. The Georgian centred low for Diego Simeone’s son to convert a simple tap-in.

Gomez was unsurprisingly hooked at half-time and replaced by Joël Matip. But the rout rolled on. Within two minutes of the restart Simeone found Zielinski sprinting into the Liverpool area unmarked and, although the playmaker’s shot was parried by Alisson, he dinked the rebound in over the keeper. The finish underlined the swagger that was coursing through the Napoli team.

Luis Díaz reduced the deficit in style when he cut in from the left and beat Meret with a fine finish into the far corner. Liverpool’s first ever goal in Naples was no cause for celebration. The visitors controlled the closing stages but had been comprehensively beaten in the sweltering Italian heat, outclassed and humiliated by a team that wanted victory more.