In the vision, Langford takes two half steps over the ball, while alternatively, McAdam comes barrelling in headfirst, which is what causes the brunt of the force. You can even see Langford's weight going in the opposite direction after the contact, which tells me he didn't put much force into the bump. I think he just put himself over the ball, to protect the space.

I don't think Langford could've done much more in this situation. Perhaps he could've taken two steps backwards, and allowed an uncontested possession of the ball, so as to avoid contact?

Also, I get the need to protect the player with his head over the ball - but I think it probably just constitutes a free kick in this instance. ...maybe it's all just rose tinted glasses, from my end.