It was a night Loris Karius can always remember – and not in a very great way. The liverpool goalkeeper created two high-profile blunders in last season’s Champions League final against Real Madrid, as Jurgen Klopp’s team came up short during a 3-1 defeat in Kyiv. He has not played a competitive game for the club since, farmed out on loan to Besiktas as liverpool spent big bucks to acquire Brazilian goalkeeper Alisson Becker from Roma.

Even now, Karius might not have fully digested the magnitude of his mistakes. The German’s blunders were broadcast all round the world within the biggest club game of the season, and he instantly became the butt of the internet’s unforgiving quips. As he drifted off to sleep the night before the final, he in all probability dreamt of being Liverpool’s hero by repelling Cristiano Ronaldo and co. in regulation time or saving the decisive penalty during a shoot-out. Instead, the evening of may 26 became a nightmare for the then-24-year-old.

“In watching that game, the goalkeeper [Karius] was showing real signs of stress and loss of concentration early on,” says Phil Johnson, a sports psychologist who has worked for a host of top European clubs, including Monaco.

“But what then happens that causes him to make mistakes that under ordinary circumstances he simply wouldn’t make? Imagine a camera scanning the pitch. That’s a description of concentration because your brain is tending to something, but the minute you focus and it takes your attention, it’s like zooming in – you’re absolutely concentrated and have focus.

“It’s a dynamic state you need to stay in. So, when something like the referee’s whistle breaks that focus, it distracts you by nature. The next thing Karius knows, the ball is coming to him and instead of catching it, he’s pushed the ball away and it’s in the back of the net. And everybody is asking, ‘how did that happen’?”

Johnson’s clarification makes Karius’ mishaps sound simple, however the man himself could have struggled to create sense of what happened – and why – within the immediate aftermath. His position on the field is critical during this tale too: players create mistakes in each game, however because the last line of defence, goalkeepers’ are punished – and therefore remembered – way more usually.

Shot-stoppers so must learn to deal with adversity. However, that’s easier said than done – significantly once the stakes are as high as they’re in matches like the Champions League final. What’s more, freak mistakes the same as the one which led to Karim Benzema’s opening goal will cause a self-fulfilling prophecy within which a player is probably going to create additional errors exactly as a result of he has made one already. Overcoming that mentality is troublesome, particularly within the heat of the moment.

“When you think about repeating a mistake because you don’t want to do it again, all your brain is saying is ‘don’t do it, don’t do it, don’t do it,’” Johnson says.

“It’s like if you’re on top of a mountain, all alone, with a piste of downhill skiing, one-kilometre wide, in front of you. There’s nobody else on the hill, just this one tree, which is half a kilometre away and I’m going down thinking ‘I’m not going to hit the tree’. But I hit the tree. Instead of avoiding it, our brains are focusing on something we don’t want to do so much that it causes us to do it.

“When we go back to this situation, our brains and physical bodies remember everything. What we remember is subconscious and our actions in those memories become automated, just like breathing. So, Karius might have been thinking, ‘I was in a high-pressure game three years ago and gave a penalty away and we lost’. If he’s thinking about something like that, his body is already reacting to it, just in the same way the skier is. It’s immobilising.”

It is not an exaggeration to say that careers have been adversely affected by a single mistake. Many players find it tough to bounce back, particularly if the incident took place in a high-profile setting. Others are able to recover from the extreme reactions – David Beckham is one example following the national vilification he had to endure after his sending-off against Argentina at the 1998 World Cup – but much depends on the individual’s make-up. With the four characteristics of trauma being hyper-arousal, numbing, intrusion and avoidance, a player’s subconscious path can make all the difference to what happens next.

“For me, the John Terry penalty miss for Chelsea [in the 2008 Champions League final against Manchester United] is interesting because he didn’t take another penalty for 18 months after that,” Johnson says.

“In that example, you see avoidance: avoiding a situation, place, person or event so you don’t reproduce the same kind of situation that got you noticed by a hundred million people. We know John Terry is an incredibly tough character and even he couldn’t manage to deal with that for a period of time.

“You might have intrusive messages in your mind instead saying ‘don’t mess up’, or a nasty feeling in your stomach that you keep pushing down to suppress unwanted negative emotions. The fourth characteristic is hyper-arousal that causes your brain to release cortisol, adrenaline and other hormones in that flight or fight response, which is the sympathetic nervous system driving the energy you need to run, stop or fight. What’s important to recognise is that it’s in performance that we are potentially at our most vulnerable.”

In Karius’ case, it made sense to remove him from the spotlight. The former Mainz net-minder was in goal for Liverpool’s first game of pre-season against Chester City, in which he spilled  the ball into his own net in embarrassing circumstances. At that point it was hard to conceive of a way back for Karius, particularly as Liverpool had already been heavily linked with Alisson.

It is possible that the German will one day return to Anfield and become a success, but being back on Merseyside and playing for Liverpool could trigger those negative feelings once more. Johnson explains that it’s not easy to reverse that brain-body memory response through cognitive behavioural therapy and points to brain spotting, a method which focuses on the core reason for the original blunder, as the best way for Karius to make a successful recovery.

“It’s not just about working with that Champions League final scenario – you look to see all of the antecedent history of things that happened before which were precursors to making that mistake. For any player, it could be another mistake, missing a sitter or getting seriously injured.

“All of those things create a conglomerate experience which the brain processes automatically and subconsciously, and that’s what would be happening to him [Karius]. In order to those feelings of humiliation and anticipating failure, you need to remove the negative experience of those memories and change the negative thoughts to stop the triggered, physical experiences.”

Whether Karius ever conquers his demons remains to be seen, but that night in Kyiv will take some forgetting.