He did not choose the starting line-up. He did not choose formation of the team. He did not choose the tactics for the game. He did not choose substitutions that were made in the game. He did not highlight the set-piece takers.

He did however jump up and down near the sidelines amd occasionaly yell at his teammates.

If that makes him a manager, then so am I a manager everytime I go to watch my local football team in the lowest league possible, because I also tend to do those things from the stands.