Wenger talks about Calum Chambers "hitting the wall"
From The Guardian:
For a 19-year-old player, he has played too many games. They all hit the wall after 15-17 games. You have to give them a breather, refresh and get them back again. At the moment, to have that responsibility in every single game is a lot on a player of that age.
I put Debuchy in [at centre-back], first of all, because he is good in the air. At Stoke, we suffered in the air. He is a defender of experience and the experience, sometimes in just one movement, can make a difference. And the defensive responsibility is a bit less on the flank.
Maybe [the players] do [communicate] but it doesn’t look like that when you look at the pictures. It’s important to have someone organising. You want somebody to take the leadership there.