Career-threatening injuries can make or break a footballer.
Every player pledges to come back stronger than before, but very few are truly able to deliver on their promise and reach the previously-attainable peaks - particularly those who are at the very top of their profession.
One such player who has endured the heartbreak, mental and physical scars of a serious setback of long-term injury and still returned to hit his dizzying heights of old is Bayern Munich and Germany goalkeeper Manuel Neuer.
Prior to the 2017/18 season, there were few football supporters who could argue the fact that Neuer had been the most influential and consistent player in his position over the past decade.
He'd achieved a save percentage north of 80% in three of his five seasons with FC Schalke 04, while subsequently completing the same feat on four separate occasions for FC Bayern. These consistently outstanding numbers spoke of a goalkeeper playing at the peak of his powers, and his match-winning contributions helped the Bavarian giants on their march to a string of Bundesliga titles, alongside lifting the 2014 World Cup with Germany.
Neuer was on a different planet to his peers, and it appeared as if nothing could stop him.
That is until the supernatural goalkeeper succumbed to a very human ailment - injury. A frustrating 2017/18 campaign saw Neuer, the innovator and perfector of the 'sweeper-keeper' role, play just three times, owing to two separate foot fractures.
"Manuel Neuer was incredible. In my time at United it is probably the finest display of goalkeeping against us."- Sir Alex Ferguson, speaking in 2011
He returned to action the next year, but minor knocks haunted Neuer, leading some to believe in April 2019 that he was considering retirement.
In fairness, his shaky performances allowed critics to sharpen their knives, with many questioning if he could ever get back to his best. The 2018/19 campaign saw Neuer post his worst numbers since joining Die Roten, conceding 23 goals in 26 matches - meaning his Bayern career-worst 'goals against per game' record jumped from an impressive 0.67 to a concerning 0.90.
Then, Neuer showed why he truly is world class; one of the top five goalkeepers in the world.
Back in tip-top condition, he has produced the best form of his life and his displays over the past 12 months have more than silenced his growing number of detractors.
Not only has he come up with clutch saves at some of the biggest moments imaginable, he's rediscovered that aura that sets him apart from so many other goalkeepers.
His resurgence has coincided with Bayern's ascension to the very top of European football under Hansi Flick; a far cry from the disastrous Niko Kovac reign that had threatened to dethrone Bayern as Bundesliga's best.
But while statistics remain a huge part of analysing any sport, Neuer's record last year is a reminder of why we shouldn't put all of our eggs in this mathematical basket. On paper, it wasn't a particularly strong return from Neuer; he conceded 31 goals in 33 games, setting a new worst 'goals against per game' percentage since his arrival in Bavaria back in 2011.
That wasn't the only record he broke, however.
Bayern's number one faced 111 shots in the Bundesliga last year - 12 more than his previous highest tally - while managing to save 84 of those efforts; another first for his Roten career. This gave Neuer an impressive save percentage of 74.8%.
All this, while languishing in seventh place in the table by early December, culminated in Bayern's worst start to a season since 1994.
That had nothing to do with Neuer though. Instead, it was evidence of what happens when a goalkeeper with the highest potential peak across all his peers, who can affect the outcome of a game more than any other shot-stopper, continuously plays to his maximum over an entire season.
Neuer's inhumane heroics were rewarded both domestically and internationally, as Bayern recovered from their nightmare start to clinch a previously-unthinkable treble.
One example of how brilliant he was - and continues to be - came against Augsburg back in March, with ten minutes left on the clock and Bayern leading by a single goal. Striker Alfred Finnbogason found himself unmarked less than six yards out, dead centre with the entire goal to aim at. From out of nowhere, Neuer flung himself in the path of his powerful shot, somehow keeping the Icelander at pay. That galvanised to Bayern close the game out, and they went on to win 2-0.
That was the only difference between one point and three, and the kind of contribution that separates good from great.
"Because life constantly poses challenges, living demands courage"- Manuel Neuer
It wasn't Neuer's only moment of brilliance, either. In June, Bayern were a goal up but a man down away at Werder Bremen. In the final minute, a wicked arching cross was headed towards the far corner by Josh Sargent, and it looked for all the world as if Die Roten would be pegged back.
But Neuer demonstrated the lightning reactions and big-game personality required to stand up and be counted, dropping to his right to palm the header away to safety. Once again, the three points remained intact solely because of him.
Those point-saving interventions helped breed a winning mentality throughout Bayern's side, and inspired them to storm to the Bundesliga title at a canter. In Europe, he was equally as decisive.
Fiick's men flew through the Champions League knockout rounds, but found themselves up against a spirited and dangerous Paris Saint-Germain in the final. In a tight, nervy 90 minutes, Neuer was the differential for the eventual winners.
"He's like a red wine that matures each year. I think he's even the best goalkeeper of all time."- Karl-Heinz Rummenigge
He kept Neymar out with a well-placed leg when the Brazilian was clean through on goal, and then defied time and the ageing process by leaping to his feet to block the rebound. He made himself enormous to deny Kylian Mbappé from close range on two occasions - spreading his body to cover the entire view of the goal - and took swift action to prevent Marquinhos from a similar distance.
It was a memorable 1-0 victory for Bayern, lifting them back to the top of European football for the first time in eight years, and completed one of the most astonishing revivals seen in the modern day.
Neuer rolled back the years on that evening, as he had done all season, proving once again that form is temporary, but being world class is permanent.