John Doolan was nearing the end of his post-match press conference when the enormity of Accrington Stanley’s Anfield adventure hit home. “Trent Alexander-Arnold put one in the top corner,” said the Accrington manager. “Federico Chiesa put one in the bottom corner … look at these names I’m talking about.” It was one of the few occasions when someone from the League Two club appeared overawed.

Liverpool, much changed by Arne Slot but packed with quality, never gave their lower-league opponents a glimmer of an upset. The milk advert remains the closest connection between the two clubs. Diogo Jota, captain for the day Alexander-Arnold, impressive 18-year-old Jayden Danns and Federico Chiesa, with his first Liverpool goal, delivered a comfortable victory for the Premier League leaders.

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But Accrington ensured this was no procession. The 2-0 half-time scoreline was harsh on the League Two club, who stand to make almost £500,000 from the tie. They twice went close to reducing the arrears in the second half. Lifelong Liverpool fan Josh Woods struck the crossbar and Donald Love missed a glorious chance in front of the 4,700 Accrington supporters.

Doolan had asked his players to do themselves justice and was not disappointed. He received a hug and compliments from Slot after the game while Alexander-Arnold, who Doolan coached as a six-year-old, also offered congratulations.

Doolan said: “I can’t speak highly enough of the man [Slot]. He is Liverpool manager and I’m an Everton fan. He is a world-class manager and he’s got a world-class team. He has invited us in for a drink and he didn’t have to do that but I’m definitely going to take him up on the offer.

“Trent turned up behind me after the game in his flip-flops and just said ‘I remember’. Then we started chatting like I’d only been talking to him last week. He is such a wonderful and humble guy. To do that shows the class he has.”

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Class told on the pitch too. Slot gave a debut to Rio Ngumoha, another academy product worthy of the hype. The left-winger, prised from Chelsea last summer, became the youngest player to start a game for Liverpool at 16 years and 135 days. Quick-footed, fast and always willing to take on his man, the young forward made an encouraging first impression. Accrington, however, adapted well to their elevated surroundings, pressing man-to-man and worked tirelessly to stifle Liverpool’s creative options.

The difference between Premier League and League Two was laid bare by the opening goal. It was the first time Accrington were out of shape and vulnerable to a counterattack, due to having a dangerous free-kick of their own deep inside the Liverpool half. When Ben Woods’s set-piece was headed clear by Kostas Tsimikas, and Nelson Khumbeni floated the ball back in to Dominik Szoboszlai, the visitors were torn apart ruthlessly. Szoboszlai and Alexander-Arnold combined to release Darwin Núñez down the right. He rolled a perfect cross behind the retreating Stanley defence for Diogo Jota to tap home.

Alexander-Arnold scored a delightful second on the stroke of half-time. The defender under-performed on his last Anfield outing against Manchester United but there was no repeat. Ngumoha was involved in the goal, cutting in from the left and having a shot blocked. Tyler Morton and Szoboszlai worked the loose ball to their captain, who swept an unstoppable shot from 20 yards into Billy Crellin’s top right hand corner. “I could talk for hours about that goal, unbelievable,” said Slot. “The biggest compliment Trent could get was the reaction of everyone after the United game.”

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Accrington refused to accept their fate and almost scored from two short-corner routines. From the first, Woods cut inside Alexander-Arnold and Tsimikas before unleashing a thunderous shot that cannoned off the crossbar. An ‘if only’ moment to regale the grandchildren with. The second came when captain Shaun Whalley crossed into the six yard box for the unmarked Love to head over from close range. He should have scored.

The lively Danns punctured Accrington’s momentum when breaking from midfield, releasing Chiesa and thumping home the rebound after Crellin blocked the Italy international’s attempted chip. Chiesa worked tirelessly for his first Liverpool goal. Crellin and a post denied the summer signing but in the 90th minute he drilled a precise shot into the bottom corner from distance. “I know it was 4-0 but it didn’t feel like a 4-0,” said Doolan. “It was brilliant.”