The Arsenal manager needs his players to be match ready and likes to push them, but admitted he and his coaches sometimes need to rein things in when they start to get fiery.
Asked to describe his training sessions in one word, he told Match magazine: “I would say ‘competitive’.
“We have to manage it and draw a line or finish a bit earlier if it ever gets too competitive, but we always need to get them close to that line.
“We need to train how we play and for that reason the training has to be competitive.”
As both a player and a manager, Mikel has participated in a number of derby games, but none more competitive than Rangers V Celtic.
Asked the fiercest derby, he said: “Probably the North London derby and the Old Firm, between his former club Rangers and Celtic.
“I was really young in Scotland and the atmosphere and level of intensity in that derby fascinated me.
“The first game was at Celtic Park and it was incredible to live that experience.”
The 41-year-old coach admitted he hates disappointing players by leaving them out of the team.
Discussing the hardest thing about his job, he said: “Probably disappointing people and, firstly, the players because they all want to play.
“Everything we do is to prepare for the weekend and to be on that grass and when you take that away from them it’s difficult.
“We all want to feel important and the only way to feel important is to get minutes.”