As a defender you are only as good as the people in front of you. Call them your barricade. I recall Patrick Vieira and Emmanuel Petit were the best I played with.
Your job as a defender facing the play is to communicate with good information, to encourage and demand. Pull people around, keep them on sentry duty and keep them protecting you and, therefore, the goal.
John Terry needs to look at the interest from West Bromwich Albion, Crystal Palace, Bournemouth, Stoke and others and choose the move that is right for him. In other words, who is going to help him the most?