Mistakes like the ones Loris Karius made here have the power to ruin people's lives, and Liverpool's goalkeeper needs protecting from the ravages of remorse.
You could see that need when Karius lay on the ground for several minutes at the end of a Real Madrid victory he helped facilitate, and had to be consoled by Gareth Bale, who beat him, ridiculously, with a speculative 40-yard shot that pinged straight through his gloves. You could see it, too, as Karius wandered the pitch alone, finally drifting over to the Liverpool end, where he raised his hands apologetically, pulled his shirt over his face, and cried.
No result, even on a night this big, is worth a self-crucifixion. Yet sport is littered with people who never recovered from calamitous errors, and live with them as demons in the head for years, for decades.
Karius will do well to save his Liverpool career, but there is no call for self-loathing. Somehow Liverpool will have to look back on this as a fine European campaign that was unable to sustain a succession of blows when it really mattered: two Karius howlers, the loss of Mohamed Salah within half an hour, and a wonder-goal by Bale, three minutes after he replaced Isco.
Bale's bicycle-kick would have beaten any goalkeeper. But his long-range dip on 83 minutes should have been safely gathered. By then Karius had already cost Liverpool a goal by trying to throw the ball out too close to Karim Benzema, who stuck out a leg and diverted in in.
Win your individual contest and the score will take care of itself, coaches like to say. After a torturous journey for their fans, at rip-off prices, Liverpool's players looked down the team-sheet of the reigning European champions and tried to win 11 battles.
Karius lost his, along with Salah - through no fault of his own. When Sergio Ramos pulled him down by the arm and made no effort to disengage as the pair fell, Salah not only dropped awkwardly and with extra force but had the hardest landing imaginable, emotionally, in a game he had started well. All that build-up, with so much anticipation, took no account of the possibility that Liverpool's star player might be removed in tears in less than half an hour.
This result was hard to take, but, in a year of struggle, to finish in the Premier League's top four, Liverpool have made a great leap. With exuberant football and a manager who is true to himself, Liverpool developed on this run to Kiev a fresh, appealing identity.
They stuck to it, too, in an opening half of vibrant effort. Liverpool started this game in hyper-active mode, determined to unleash their front three. Real Madrid hated it. They come to these occasions to control and dictate. They were not built to be hustled and rushed. But by half-time Jurgen Klopp's team had already made an important declaration. Their high press can be effective at this very highest level. The style of play that carried them here is a threat to anyone.
Always with Liverpool, the present becomes a version of the past, so that Klopp must be the reincarnation of Bill Shankly, and carry the club's history on his back. That heritage has its uses - and heaven knows Liverpool fans are quick to connect with it. Their banners are closer to essays than slogans. They speak of family, Shankly's ideals and unbreakable bonds. Yet the game moves too fast for past eras to be picked from the history books and reheated. Liverpool have no choice but to write a new story in the age of £200m footballers and clubs owned by nations.
Kiev was a good place to show they can compete with all this. Matching Manchester City domestically was beyond them, but European knock-out football is another route to glory, and Liverpool have taken it, with wins over Porto, City (spectacularly) and Roma. This Cup run was of huge long-term value to Liverpool's owners. The club's openness and grown-up media strategy were a lesson to other top Premier League clubs and marked them out as an organisation who want to communicate and promote their image.
Before the game itself, Klopp spoke of Liverpool's "big-balls football". No challenge to Real Madrid is possible without boldness. The intrepid approach swept Man City aside, but Zinedine Zidane's men are specialists in showpiece games. They are are monsters: talented, adaptable and physically strong. In American business terms they are 'closers'.
This game was ratings gold, but Uefa can no longer hide from the ridiculous logistical challenges presented when cities are unable to cope with such influxes. Kiev's airport could not accommodate the demand for landing slots. Its hotel prices went through the roof. And these are not parochial gripes. For last year's final in Cardiff, spectators were forced to take rooms as far away as Bristol and Bath. The travelling fan is treated as meat.
At least they were entertained here, until the game took a dark turn, with Karius' misery. Klopp hugged him on the pitch, but could not save him from his thoughts.
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