“Despite all of these hours of tennis in the course of all these years — including another one and a half compelling ones on Tuesday, which ended with Serena beating Venus in three sets and continuing her march toward the calendar Grand Slam — we aren’t much closer to an answer.” Ian Crouch on the odd and often upsetting experience of watching the Williams sisters compete against each other. (During yesterday’s match, they couldn’t have looked much more unhappy.)

+ Grantland: How Venus Williams helped create Serena.