Joris is learning! He just keeps quiet and let Jamie talk. Specially since it looks as if the coach looks entirely uninterested in the whole situation-

Or anything outside of what he considers his job.

"That's no reason for borrowing other people's, or for skulking in here. Get out on the field, both of you. You three get out there too."

Which seems to be making everyone go out and play what-ever-game that is out there, even if he recognises them as students or not.