It was January 2017 and, having started just three cup matches for his boyhood club, an 18-year-old was about to start for the first time in the Premier League in arguably English football's biggest fixture.
An injury to then first choice right-back Nathaniel Clyne saw Trent Alexander-Arnold named on a top-flight teamsheet for the first time as Liverpool travelled to face arch rivals Manchester United.
While it wasn't the most memorable match by any standard, with Zlatan Ibrahimovic netting a late equaliser to James Milner's first half penalty, the teenager put in an assured display on his full league debut.
United unsurprisingly targetted the majority of their attacks down their left hand side, but the fact that Alexander-Arnold's opposing winger Anthony Martial was replaced midway through the second half was testament to the youngster's showing. Outfoxed by the Frenchman a couple of times in the first half, the full-back grew in confidence by the time Martial was replaced by Juan Mata, and made three tackles and two interceptions in total during the match.
It understandably wasn't the level of attacking display for which Alexander-Arnold is now renownd. Alexander-Arnold would start just one more league game that season, hauled off at half-time as Klopp fielded an experimental line-up and formation at Stoke.
That said, Jurgen Klopp has this week stated that he recognised even then that the academy graduate had a future in the first team
"The things he is showing, I saw. That it is possible for him to be a proper Premier League player," the Reds boss stated.
"I remember the walk we had when I told him he would play (against United). He didn’t look too surprised, not that he wasn’t nervous. I don’t remember the game but it was an important first step for him and an important first step for us."
It was indeed, with the England international pivotal to what has been a remarkable progression over the last 18 months or so.
The 21-year-old is an extremely progressive player, and as such his defensive numbers don't always inspire great confidence. He's been dribbled past more often than he has made a tackle this season, but to all extents and purposes, Alexander-Arnold's role in the side is to force overloads in the attacking third.
With Mohamed Salah - who usually operates in front of the right-back - given the licence to cut in onto his left foot and get into scoring positions whenever possible, Alexander-Arnold has free reign down the flank more often than not.
As a result he ranks among the top five players in the league for accurate passes in the opposition half (283) and successful balls into the final third (83). Meanwhile only peerless playmaker Kevin De Bruyne has created more chances, both in total (29) and from open play (23) than the Liverpool star (28 and 19 respectively).
Most chances created from open play in the Premier League:
— WhoScored.com (@WhoScored) October 18, 2019
Kevin De Bruyne - 23
Trent Alexander-Arnold - 19
Jack Grealish/Riyad Mahrez - 18 pic.twitter.com/tv6436wE0F
The Reds' closest rival in overall key passes is Mo Salah, who is 12 back on 16, while Alexander-Arnold has delivered more than twice as many accurate crosses (17) than any teammate.
It's not unheard of for a full-back to be the most creative player in a side - Joshua Kimmich was similarly influential in the attacking phase for Bayern from right-back - but it's not conventional either. Kimmich has this season reverted to what was initially his favoured central midfield role this season, and it has been mooted that Alexander-Arnold could adopt a similar position in the coming years.
However, for the time being, the youngster's skill set is unquestionably best utilised where he is for the time being. At 21 - having played in successive Champions League finals and emerged victorious in the latter - he is unquestionably among the very best full-backs in world football. With Kimmich seemingly set to take up a midfield berth for the considerable future, some would argue he is the very best, even if he is yet to cement a spot for his country.
Gareth Southgate perhaps has some reservations over the defensive side of his game in a side that aren't nearly as free-flowing as Liverpool. Perhaps more pertinently he also has a great deal of faith and gratitude towards Kieran Trippier following his role in last year's World Cup campaign.
It's surely time to look to the future ahead of the European Championships, however, with Alexander-Arnold capable of earning legendary status for both club and country.
The last Englishman that had the most legitimate claim to be the best player around in his position was arguably Ashley Cole. Less than three years on from his full league debut, Alexander-Arnold will return to Old Trafford as the best candidate to be the next, if he isn't already.
