As the youngest team in Liverpool’s history celebrated reaching the fifth round of the FA Cup it was not hard to imagine Jürgen Klopp, laptop and beer at the ready, affording himself a wry smile on holiday. His gamble, his disrespect, his principled stand against football congestion, call it what you will, had paid off. Liverpool’s youth made their own point - they were far too accomplished for Shrewsbury and worth considering at Chelsea next time out.

Another Anfield victory ended with Liverpool’s manager punching the air in front of the Kop but, with Klopp absent, it was Neil Critchley who revelled in the moment and a performance that obeyed his pre-match instructions. “The boss was in touch this afternoon with some words of advice and encouragement,” revealed Critchley. “Play the Liverpool way, go for it. That is what the first team do. This is how we play, this is what we stand for and you had better be ready for it. We had a message from the staff afterwards that he is absolutely delighted with the performance and buzzing.”

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Progress was secured courtesy of a calamitous own goal by Shrewsbury defender Ro-Shaun Williams and abetted by VAR’s decision to disallow Shaun Whalley’s header for the visitors, but there was no disputing the merit of Liverpool’s win. The average age of Liverpool’s starting line-up was 19 years and 102 days. It featured four debutants in Adam Lewis, Liam Millar, Jake Cain and Leighton Clarkson. They were forced to wait 15 minutes before playing in front of a capacity Anfield crowd for the first time with kick off delayed by a crash on the M62 that impacted on match traffic. They handled the step up effortlessly while Shrewsbury floundered badly. Sam Ricketts’ League One side did not produce a shot on target as they failed to rediscover the energy and belief that brought them back from two goals down in the first encounter.

“I feel for the players,” the Shrewsbury manager said. “They worked so hard to get here but our 39th game of the season caught up with us. We couldn’t get near them or impose ourselves on them. Maybe we should have a winter break.”

Curtis Jones became Liverpool’s youngest captain as he led the team out a week after his 19th birthday while first team players holidayed in the likes of Dubai, Maldives and Miami. But not James Milner, of course, who was a vocal presence behind Critchley in the dug-out and in the dressing room. “He trained with us yesterday and asked whether he could come along, it was very respectful to ask,” said Critchley, Liverpool’s under-23s coach. “He was animated, he was vocal, I can’t thank him enough.”

Liverpool’s teenage skipper, 16-year-old Harvey Elliott, Neco Williams and midfield anchor Pedro Chirivella, who all started the humiliation of Everton’s first team in round three, were prominent as the hosts dictated proceedings. Their superior technique and natural confidence was obvious although opportunities to make it count were limited in the first half. Jones drilled a free-kick straight at goalkeeper Max O’Leary. Williams went close with a low drive that sailed wide of the far post and saw another effort blocked by Scott Golbourne.

Liverpool were composed, sharp and feeding off the support of the crowd. Shrewsbury were remarkably flat by comparison. Even taking their struggles in League One into account, the visitors were underwhelming. They may have been unable to rise to the occasion due to Liverpool’s dominance of the ball but Shrewsbury failed to make their physical advantage count and rarely threatened Caoimhin Kelleher’s goal.

Williams had the majority of Liverpool’s chances despite operating on the right of defence. Trent Alexander-Arnold’s spirit of adventure has evidently rubbed off. The Wales Under-19 international swept a half volley over before being denied by O’Leary’s instinctive save with his feet following an incisive pass from Elliott.

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Ricketts introduced Daniel Udoh for the injured Callum Lang and the substitute made an immediate impact, spinning away from Williams and crossing for David Edwards to force a fine close range save from Kelleher. The rebound looped up for Whalley to convert but then came the dreaded wait for VAR. It found Udoh had been offside in the build-up and the celebrations switched from the Shrewsbury end to the rest of Anfield as the goal was disallowed.

Edwards urged his teammates to keep their heads amid the deflation. Unfortunately for Shrewsbury and their hopes of a lucrative trip to Stamford Bridge, Williams used his with dire consequences. There were 15 minutes remaining when O’Leary threw the ball towards substitute Jason Cummings, Shrewsbury’s two-goal hero last time out, but Liverpool’s Williams intercepted easily. He returned the ball deep into the Shrewsbury area where the central defender, unaware that his goalkeeper was coming to collect, headed over O’Leary and into his own net. The kids were through, deservedly so.