You don’t arrive at the U.S. Open thinking you need a cap. But by the time you’ve walked from the subway to Arthur Ashe Stadium, you’ve begun to wonder why you haven’t got one. The merchandise starts to multiply: hats, sweatshirts, shopping bags, Ralph Lauren gear slung over shoulders and draped over arms, carried with all the satisfaction of the recently persuaded.

The Open is very good at this. Everything looks less like merchandise and more like a uniform. I bought the cap.