Hints on Association Football. Centre Half as Third Back. The modern centre-half is largely a defensive player adopting the role of a third or middle back. He rarely moves out of his own half of the field and his special duty is to shadow the opposing centre-forward, who lies well up ready to seize a chance to break through. Again, he is usually on guard in the penalty area (the danger spot) not only covering the centre forward, but being prepared to use his head when the ball comes over, and generally giving assistance to the backs. In lying so far back it is not possible for him to do much attacking work. Undated.