Wimbledon has required players to wear almost entirely white since the tournament's Victorian origins.

Wimbledon’s all-white dress code traces back to Victorian tennis etiquette, when white clothing was considered proper and, practically speaking, helped hide sweat stains, which were seen as improper to display in polite society. Unlike the other three Grand Slam tournaments, which allow colorful outfits, Wimbledon has kept a version of this rule intact for well over a century.

The modern rule is notably strict: since a 2014 update, the tournament’s regulations specify that competitors must wear “almost entirely white” clothing, with only a thin trim of color permitted, and this applies from the moment players arrive at the grounds, not just during matches. Officials have been known to send players back to change, and even undergarments visible beneath tennis whites are subject to the rule, making Wimbledon’s dress code among the strictest in professional sports.