Klopp has worked with some outstanding footballers in his managerial career, including the likes of Virgil van Dijk, Sadio Mane and Mohamed Salah at Liverpool, but claims Lewandowski is out on his own.
Lewandowski was signed by Klopp for Borussia Dortmund in 2010 and they won two Bundesliga titles together as well as reaching the Champions League final in 2013.
The Poland international joined Bundesliga rivals Bayern Munich the year after and has scored an incredible 284 goals in 323 appearances for the German giant and is now considered one of the best, if not the best, striker in world football.
When asked to name the best player he’s ever managed in an interview with Sport Bild, without hesitation Klopp said: “Robert Lewandowski.
“It actually won’t be fair to say that about any other player except Lewy.
“What he has made out of his potential, how he pushed himself to become the player he is today, that’s extraordinary.
“If every player has a development similar to Lewandowski, when I first saw him at Lech Poznan, then the football world would be completely crazy.
“All players would win all their duels, the full-backs would complete all their crosses, the midfielders would be strong in one against ones, the wingers would tackle and play precise long balls.
“Lewandowski made every step he had to make to become the goal machine he is today.
“He knows exactly what to do in every situation. He’s an absolute machine.
“I would like to thank him and all the other players who made it look like as if I’m a very good coach.”