It ain’t over till . . .

For the New York Yankees, tradition is both an identity and a marketing strategy. Their tasteful home uniforms with those trademark blue pinstripes, introduced more than century ago, have been essentially unchanged since 1936. An innovation somehow occurred in 1928, when the Yankees became the first team to put numbers on jerseys—but names, now included by virtually all other teams, have been a bridge too far. They enforce an “appearance code.” Players traveling with the team must wear sports jackets; mustaches must be neat; beards are forbidden; head hair may not touch the collar. They worship ancestors. The first baseball team to retire a player’s number (Lou Gehrig’s “4,” in 1939), they have since retired twenty-one more; all the single digits are now taken. They put headstone-like monuments to the legendary Miller Huggins, Babe Ruth, and Gehrig in deep center field of old...