I just had this thought of Steve McQueen in the film Great Escape, locked up in solitary confinement bouncing his ball up against the cell wall.
Do you think Boris Becker is doing the same. :)
My guess is he's busy signing autographs and working out which of the cons runs the prison so that he can pay to be under his protection. Bound to be one or two there who want to make a name for themselves by having a pop at BB.