The Guardian's football trivia column The Knowledge tackles a reader's question about when fans first began wearing replica kits, tracing the murky origins of a now-ubiquitous football tradition. While there is no single definitive answer, the piece credits Leeds United and kit manufacturer Admiral with producing the first official replica kit in 1973-74, following a deal struck between Leeds manager Don Revie and Admiral owner Bert Patrick, though initially only children's sizes were sold.

The article details how Admiral paid Leeds £7,000 to redesign their kit and display its logo, with children's replicas selling for around £5, and by 1977-78 the trend had spread to 84 of 92 English league clubs as well as several Scottish and German sides. It notes earlier, unofficial precursors such as Umbro's 1959 "Umbrosets" featuring Manchester United, and explains that the 1968 Design Copyright Act likely delayed official replica sales by protecting registered designs. The first adult replica shirt is identified as Admiral's 1982 World Cup England kit.