Arsenal defender Sead Kolasinac has hailed the influence of German coaching guru Norbert Elgert.
The 60-year-old Schalke under-19s coach has been in his role since 1996, overseeing the development of a staggering amount of top players.
Kolasinac told Arsenal magazine: "Norbert Elgert is somebody you need to meet to learn why he has such an impact," said Kolasinac, who joined the Gunners from Schalke in the summer.
"It's not just Mesut and myself who have benefitted from him, there are lots of players both in the Bundesliga and elsewhere who managed to make the step to becoming a professional because of his help.
"He took me to one side and told me that if I pulled in the right direction, listened to him and did as instructed in the two years I had with him, I'd have the opportunity to break into the senior team.
"When I started working with him, I started to notice the progress - I was improving, tactically I was getting better and my game in general was getting better.
"You go to him as a boy and he moulds you into a man, helps you build your personality. He does that really well.
"You notice during every training session how much he loves his job. That's why I think Schalke have been so successful at generating young players for the first team.
"A large portion of that is down to Norbert Elgert."