Tactics nerds may just have found a new God
Marcelo Bielsa, Marseille Manager
From his wiki-page:
A fanatic of football videos that he adds to his collection, Bielsa on occasion checks pitch measurements by pacing them out before deciding on a particular formation. He allocates separate training times for different parts of his squad. Former Argentine national team captain Roberto Ayala and defender under Bielsa stated "Sometimes we wouldn't see any of the strikers, because he'd have them training at a different time, and it was the same with the midfielders."
He is known for watching and collecting numerous football videos to the point of obsession. He edits and analyzes each video for each individual player. He also utilizes statistical software and other technological tools to prepare for games. John Carlin, an English journalist, has stated that Bielsa "has the most cultured library of soccer in the world."
Athletic Bilbao's striker Fernando Llorente said in an interview "At first he seems tough and he may even annoy you with his persistence and don't-take-no-for-an-answer resilience, but in the end he is a genius." Barcelona's Pep Guardiola called him the "best manager in the world" in 2012.
As Bielsa refuses to grant exclusive interviews, the press conference has become his preferred method of communication. He has been known to field every last question from the assembled media during these gatherings. If the talk turns to the intricacies of the game, a three- or even four-hour press conference is possible.