Rule one of Wimbledon show court etiquette: back Andy Murray (usually politely, more occasionally volubly). Rule two: ignore rule one when he is playing Roger Federer.
Up on the Hill and in living rooms around the country, things are different. But in the rarefied air of Centre Court it is still the appearance of the Fed Express, serving here like a train, that makes many of the pastel-clad masses go weak at the knees.
Centre Court at Wimbledon, for all its maddening peculiarities, can usually be relied upon to fuel Murray with the self belief that allows him to play his best tennis.