Baseball stirrups

Stirrups are uniform socks commonly worn by baseball players up until the mid-1990s, when major-league players began wearing their pants down to the ankles, setting a trend soon picked up by players in minor and amateur leagues. Until then, stirrup socks had been an integral part of the traditional baseball uniform, giving them a distinctive look. A high sock was needed because baseball players wore knickerbockers ("knickers"), worn by many boys in the late 19th century and into the 20th century. The stirrup socks served to display team colors, stripes or team logos. For example, for several years the Minnesota Twins wore navy-blue stirrups with "TC" on the side, for "Twin Cities", and in 1987 an "m" was placed on side. The Houston Astros wore navy blue stirrup socks with a white star on the side. The stirrup sock colors were also the basis of team names, including the , Boston Red Sox, and Chicago White Sox. For these reasons, traditionalists lament the recent "sockless" look in baseball uniforms.

Stirrup socks are worn on top of long socks called "sanitaries," usually white in color. This is because early color dyes in the outer stirrup sock were thought to pose health issues, as well as the fact that the inner, less expensive white sock could be changed more frequently. The stirrup sock lacked a foot, instead having a loop ("stirrup") which fits within the instep of the foot. Over the years, the stirrup loop tended to get longer, exposing more of the white undersock, thus creating a look unique to baseball.

However, by the 1980s many players were pulling the loop so high that only the white undersock and the loop itself showed - the rest of the game sock being hidden by their pants. For many years teams had enforced rules so that uniforms were worn "uniformly", including team socks. For example, Leo Durocher, longtime manager of the Chicago Cubs, had a measuring stick in the clubhouse. Players were required to match the length of their stirrup loops to this stick at about 4 inches, exposing only a small part of the white sanitary. Increasingly lax regulation of uniform codes by Major League Baseball eventually contributed to players ignoring the traditional look.

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Wikipedia