“We’ve conquered all of Europe, we’re never gonna stop,” goes the opening line of Liverpool’s version of Allez, Allez, Allez. The song needs updating along with the list of honours on the champions’ wall at Melwood. Jürgen Klopp’s European champions never stop and, on a night of high drama, quality and controversy in Doha, they conquered the world, too.

Roberto Firmino broke the hearts of his compatriots from Flamengo with the decisive goal in extra time as Liverpool triumphed in the Club World Cup. The Brazil international missed two clear openings in normal time but finally secured a title that had eluded predecessors in 1981, 1984 and 2005. Klopp’s team have achieved what no other in the club’s illustrious history have managed before. Plus a little pay-back for defeat by the Brazilian club in the final 38 years ago.

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Then, Liverpool had travelled to Tokyo on a jolly. This time they came to Qatar determined to write their names in Anfield folklore and validate the decision to bring a full-strength squad at the expense of the Carabao Cup. Klopp’s players delivered. Champions of Europe in June and champions of the world in December and, as things currently stand, champions of England next spring; a glorious hat-trick beckons.

The importance of victory could be heard as Jorge Jesus, the Flamengo coach, was claiming in his post-match press conference that the Brazilians were the better team in normal time. His words were drowned out by the sound of “Campiones, campiones, campiones” bellowing from the Liverpool dressing room. The only setback was an ankle injury to Alex Oxlade-Chamberlain that resulted in the unfortunate midfielder leaving the stadium on crutches.

It was an enthralling final between two well-matched, positive and high-calibre teams. Flamengo had their chances too but, before being punished by one Brazil international in Firmino, they were thwarted by another in the imposing form of Alisson in Liverpool’s goal.

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The Club World Cup was decided not only by Brazilians, however. Jordan Henderson was outstanding in Liverpool’s midfield and supplied the cutting pass that led to Firmino’s winner. Behind him, Joe Gomez produced his best display of the season and a key role in a crucial clean sheet.

Normal time ended in bewildering fashion when the Qatari referee, Abdulrahman al-Jassim, awarded Liverpool a stoppage-time penalty for a foul by Rafinha on Sadio Mané as he shaped to shoot. VAR showed Mané had been clipped a fraction outside the penalty area and, following a lengthy review by the on-field referee, the penalty and the booking for Rafinha were overturned. Mané may have shot before contact was made but that did not explain the drop ball that followed from the referee. Flamengo were unable to make the most of the reprieve, although the substitute Lincoln missed a fine chance to equalise in the final seconds of extra time.

Liverpool knew what they were up against from the moment they emerged for their warm-up to piercing whistles from the estimated 15,000 Flamengo fans who had travelled. The noise from them was incessant, although all that really mattered to the European champions was Virgil van Dijk being present to hear it. The commanding central defender was back in the side having missed the semi-final through illness. His first touch sent the ball quick and high over the top of the Flamengo defence. It was no accident. Liverpool were clearly under instruction to exploit their opponents’ high defensive line at every opportunity and should have punished it twice inside the opening five minutes. Firmino, however, squandered a clear opportunity when sent clean through by Trent Alexander-Arnold and Naby Keïta did likewise when teed up by Mohamed Salah.

When Alexander-Arnold flashed a low drive just wide of Diego Alves’s goal from over 25 yards seconds later it seemed only a question of time before Liverpool’s commanding opening paid dividends. It was a false dawn. Flamengo always looked dangerous given the quality of Bruno Henrique, Éverton Ribeiro and the prolific marksman Gabriel Barbosa but were contained in the opening exchanges by the relentless pressing of Liverpool’s midfield three. Gradually, however, they began to turn the tide, with Gerson and Willian Arão increasingly influential in midfield. Klopp’s visible anger on the sidelines was not solely the result of al-Jassim’s erratic refereeing. The Liverpool manager’s sprint down the tunnel as soon as the half-time whistle blew was a clear sign of irritation with his team too.

Liverpool’s frustration had mounted as the first half progressed. Salah copped an earful from his manager for squandering a glorious chance to punish Flamengo on the counterattack. They were refused a clear free-kick on the edge of the penalty area when Keïta played a one-two with Salah and was taken out by Filipe Luís and Mané, uncharacteristically quiet until late in the game, was booked after tangling with Rafinha.

The second half opened with a flurry of chances and a repeat for Firmino. Collecting Henderson’s chip forward the striker flicked the ball over the head of Rodrigo Caio and steered a half-volley beyond Alves. It would have been a beautiful goal but Firmino’s shot struck the inside of a post and rolled across the goal to safety. Salah went close with an improvised touch on Alexander-Arnold’s driven cross into the area before Flamengo responded strongly. Alisson produced a superb save when Ribeiro created a first chance of the night for Barbosa. His powerful shot was destined for a bottom corner until Alisson’s strong right hand tipped the ball wide.

Alisson thwarted Barbosa again when the Brazil forward executed a spectacular overhead kick but Liverpool finished stronger and, in extra time, Flamengo’s 79th game of 2019 caught up with them. The decisive moment was created by Henderson’s superb ball through the heart of the Brazilian defence to Mané. He squared for the unmarked Firmino, who cut back inside Caio and Alves before beating Rafinha’s despairing dive on the line with a cool finish. The booking he received for removing his shirt in celebration was worth it. “Blessed” read the tattoo across the goalscorer’s chest. Liverpool know exactly how that feels.