David Wagner has admitted he did not expect to be facing Jurgen Klopp, so soon in the Premier League.
Master will face apprentice in the match between Liverpool and Huddersfield, it is the first meeting between them.
Wagner and Klopp played alongside each other at Mainz in 1991, before they worked together at Dortmund.
“It is extraordinary because he is my best friend,” said Wagner via the Telegraph.
“But the real extraordinary story is that Huddersfield are playing Liverpool in the Premier League.”
“Did I think I would play him in the Premier League two years after arriving here? It is at least 10 years sooner than I ever dared dream,” Wagner continued.
On Klopp and Liverpool, Wagner said he knows what to expect, adding: “For the first time, my very good analysis team came to me and I tell them, ‘Don’t tell me, I know’.
“It makes it easier to play them because I don’t have to invest too much time in analysis, I know all I need to know about them and how he will set them up.”