Former Mainz manager Kasper Hjulmand is amazed by Loris Karius' success at Liverpool.
Karius joined Liverpool in the summer of 2016 for £4.7m, ending his five-year spell at the Bundesliga club.
Hjulmand said: "In Mainz, it was not written in the sun, moon and stars for me that he would end up in a big club like Liverpool.
“He has a wonderful mental strength, and he has not been influenced by the kinds he has received.
"At that time, I thought his game with his feet was a bit too bad and that he was a little too much on flat feet.
"But I can see that he has developed it really fine without ever increasing his strength."