Trent Alexander-Arnold’s error costs Liverpool but he remains essential

As the final whistle blew at the Stade de France Trent Alexander-Arnold was closest to the Madrid bench, swaying to one side as the white shirts came haring on, gripped with an entirely familiar delirium. At which point Alexander-Arnold just stopped.

For the next five minutes, in the middle of the smoke, the pounding noise, the crackle of static across this vast craning bowl, he stood completely still at the edge of the centre circle, bent forward slightly as though in physical pain. Jürgen Klopp came across to offer a hug. A phalanx of photographers skirted past tactfully. Eventually, as the Uefa plinth was rigged into place, he just lay down alone on the turf and held his head.

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Oh, Trent. There will of course be a temptation, one that will be eagerly taken up, to single out Alexander-Arnold in the wake of this 1-0 victory for Real Madrid, to linger on the error of defensive cover in the buildup to the only goal of the game, a mistake that will be flagged and sighed over, subjected to the light pen of doom, the gifs of death, the eight-shot still montage of shame.

Rightly so on the face of it. This was a game of half-chances and collisions and condensed space – all apart from that one second-half moment when it suddenly came apart. For Liverpool the story of this season will now be one of glory, but also of falling short, or rather seeing others fall just a little further. One point to lose the league, one goal to lose this final. Close, but only two cigars.

There is though another side to that equation. Madrid are exceptionally good at this, so cruel, so surgical in the way they find and prey on weakness. They’ve done this to every single one of the Premier League’s top three now. This is a thing that happens.

And secondly, Alexander-Arnold is also how Liverpool win. He is how they got here, what this team is built for. Alexander-Arnold is the project. For an hour, as so often, he looked like the way Liverpool might win this game.

Then suddenly he wasn’t; was instead that other thing. You could see it coming, too, and in the most agonising way. Vinícius Júnior had barely touched the ball in the opening 10 minutes after the break. As Madrid broke through the centre of the pitch he was way out wide, stuck to the chalk line. He held his position, held it a little long, daring himself to stay out there as the ball was funnelled to the opposite side.

Watching this there was an urge to stand up and shout and point. That white shape on the touchline, 40 yards from the ball, sprinting now, still completely untracked. That’s the danger.

Through all this there was the oddness of Alexander-Arnold’s reactions. Not his position, close to his centre-half, covering that hole. But his failure to look behind him, the sudden blankness, as though simply refusing to acknowledge that the man in white could exist. If you can’t see it, it can’t hurt you.

The cross from Federico Valverde split the six-yard box, and Alexander-Arnold finally looked, in time to see the net billow in front of the Madrid fans.

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In that moment the day simply slid away from Liverpool. The first few seconds brought a kind of saloon bar brawl on the left, as Liverpool pressed furiously high. And Alexander-Arnold was very good in the opening 20 minutes, playing without fear, strolling, watching , then suddenly appearing high up the pitch, pressuring the game into his spaces.

He forced the first real chance of the game, producing a lovely dribble, surge and spin, easing his way past Ferland Mendy, crossing for Mohamed Salah to shoot, scruffily. Moments later there was another slick, smart interchange, another Salah shot. Sadio Mané spun and clipped a shot on to the foot of the post. This is the best of Liverpool, those waves of attacks that add up, wear you down, induce a kind of mental disintegration.

In between Madrid played like a team that wanted this thing to go cold. They slowed the ball down. They rested. They let the lactic acid fade. This is how Madrid win, in moments. Systems? We are a system. There were some early cross-field passes into he Vinícius zone, what was to come. It is an odd quirk that Liverpool have a midfielder who was a right-back covering their right-back who was a midfielder. But Alexander-Arnold looked solid, looked fine, looked in control, right up until the moment he didn’t.

Even after that he was still Liverpool’s most convincing attacking threat on a night when too many parts looked below their best. That edge has become a blunted late in this season of 63 games and endless jeopardy.

By the end Alexander-Arnold’s contribution to this game seemed to capture something of Liverpool season. It is no secret he is both a flawed footballer, and a brilliant footballer. It isn’t enough to say, well, this is the trade-off, this is the nature of modern full-backs. Nothing in the ability to cross and pass and fade the ball across the field like a divine being means you can’t also look behind you. Alexander-Arnold has an angel on both shoulders.

Over time it is his brilliance, the good part, his thrust, his net gains that drive this team on from the right flank. But there will also be moments like this, fine margins, high-wire defence, flashes where the day seems to be on the verge of falling apart. And then sometimes it does. The pain of that moment at the end will hopefully fade with time. It is the nature of that balance, the risk and reward. There will no doubt be plenty more in the way of glory.