Europe's top clubs seeking the next Mesut Özil or Julian Draxler are beginning to wonder whether increased investment in their youth academies really pays off, when there is one club gazumping them time and time again.

Schalke 04 have a reputation for delivering talent after talent from their revered Knappenschmiede production line. Its success is so well documented that it has become more of a showcase of some of the world's best talent; a sort of one-stop shop for Europe's biggest clubs when they begin their search for the next best thing in football.

Behind the extraordinary success of the Gelsenkirchen club's inimitable academy is Norbert Elgert – the man who launched the careers of many a world champion, and has not stopped yet providing some of the rawest talent the game has to offer as coach of the Bundesliga club's under-19s.

Watch: Schalke's famed Knappenschmiede

Leroy Sane, Mesut Özil, Julian Draxler, Manuel Neuer, Leon Goretzka – the list goes on. That is a combined €228 million worth of talent, without putting a price on Goretzka – who joins Bayern Munich on a free transfer in the summer – all to have been lifted from the gold mine which is Schalke's gilt-edged academy.

"No doubt that would be a team who would be capable of seriously challenging Bayern," Elgert told the SID agency on the calibre of players he has nurtured and then seen fly the nest. "Many players have left because they want to be playing regularly in the Champions League, and they've also taken the opportunity to earn more."

Real Madrid, Arsenal, Juventus, Manchester City, Paris Saint-Germain, Liverpool and Bayern Munich are the perennial Champions League pretenders all to have benefitted from Elgert's work, acquiring gems which have been hammered and chiselled into effusive diamonds by Schalke's under-19's coach, who has a distinct knack of forming stars.

A laid-back Leroy Sane nearly missed the train to stardom until Elgert pointed him in the right direction. © DFL DEUTSCHE FUSSBALL LIGA

Take Sane, for instance. The Manchester City wing wizard would probably not have been such a household name had Elgert not worked his magic and ensured fame did not see him get ahead of himself. "You've got to have character, personality, desire and be willing to put in the effort," Elgert said. "I had to bring [Sane] off after 25 minutes when he came back from playing with the first team once because I was not pleased with his effort.

"Let's put it this way: Leroy was and is a very relaxed, laid-back lad. His attitude was always good, but not quite optimal. We had to work on that, and this work – which he was also convinced by – has now paid off."

Sead Kolasinac, Joel Matip and Max Meyer have also been blooded by Elgert during the past two decades, and the 61-year-old does not forget any of them, although he insists he is only a cog in one of Gelsenkirchen's best machines. "It's a great feeling when you see you are making a difference as a coach," he said. "It moves me a lot, bit I must stress that the Knappenschmiede is no Norbert Elgert show – we've got plenty of outstanding workers here and I'm just pleased to be one of the stones which forms the mosaic."

Eigert has been celebrated for his successes with Schalke's youth team, and for the calibre of players he has helped produce. © imago

So who exactly is this man who has brought 80 players – at the last count – into the professional game? Elgert made 57 Bundesliga appearances and scored 12 goals since making his Schalke debut in 1975. 21 years later, after hanging up his boots, he was given the reins to the under-19s in one of the wisest moves Schalke ever made.

His own career would not even have lasted as long as it did had it not been for two characteristics Elgert places particular emphasis when he spots a future star. "My career was really over," he said, recalling the time doctors discovered one of his kidneys was failing – not that it stopped him. "I was never as healthy as others, but with the right attitude and a lot of willpower, you can achieve a lot."

That wisdom has been passed on from start to star, including current Schalke captain Ralf Fährmann, who first met Elgert when he was a 15-year-old arriving in the Knappenschmiede from Chemnitz, and still recalls the first lesson he was taught. "I was experimenting a bit with my hairstyle at the time and the coach said: 'if you want to catch the eye, then you need to do it with your performances, not your hair.' The next day, I shaved it all down to two millimetres because when the coach says that, you do it."

Four of Germany's 2014 World Cup winners had learned the ropes under Elgert. © imago

What Elgert says certainly carries weight, and that is just one of the many reasons why four of Germany's 2014 World Cup winning squad – Draxler, Özil, Benedikt Höwedes and Neuer had all worked under him.

"Coaches should be more than just deliverers of technique, tactics and condition," Elgert told N-TV. "Values like respect, honesty, willingness to help, tolerance, fairness, togetherness and humility are more important than ever in how things currently go at such a high speed. Reach for the stars by all means, but keep your feet firmly on the ground."

When Europe's top clubs reach for the stars nowadays, Gelsenkirchen is invariably the first place they look, thanks to Elgert.

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