Arsenal boss Arsene Wenger has given a rare insight into how he technically judges a player.
In an interview with Total Youth Football magazine, Wenger explained that the speed of a player's passing and the direction - down to split seconds - is all important to him.
"It works well with your tactical observations, too. You see that a guy never loses the ball, so you look at the number of times he passes the ball forward. You can get to the point where you can say, 'I prefer the one who loses the ball a bit more but tries to play it forward.' It is a concrete observation."
Wenger says the new football software now available to managers has changed the face of coaching.
"In the past, it was just about feelings, opinions," Wenger explains. "So I thought, 'That's not good enough,' and I wanted to know a little bit more. I am always in the situation where I have to judge people, and the more concrete objective numbers you have the better you can achieve that.
"For me, it's an integral part of the game. And I must say when I come in the next morning after a match I am like a guy who is after his doses! He needs to inject! I have a feeling of a performance and then I want to check if that feeling is right or not. So I get all the numbers I can."