I once saw Danny Cullip shout, very loudly, in the ear of a striker he was marking. When the ball came over the poor bloke was still rubbing his lobe, in some pain. I've never seen anyone do that before but it certainly worked.
I see him most mornings driving his Range Rover with its distinctive number plate with a phone to his ear
Not occasionally, but more times than not, you would have though he could afford a hands free kit.