Why are the referee's cards (caution and expulsion) yellow and red?

 The new season of the Italian football championship starts today. While wishing all the teams and fans a good season, we would like to share with you some of the history and curiosities of the football world.

In the late 1960s, Englishman Ken Aston, a former referee turned FIFA executive, introduced an innovation that has since become a staple of the sport - the use of yellow and red cards. These vibrant signals, indicating cautions and dismissals respectively, were first unveiled at the 1970 World Cup in Mexico and were officially incorporated into the football rules by 1973. Aston's inspiration struck while waiting at a traffic light, symbolizing the universal reach of football's influence.

Aston continued to revolutionize the sport, introducing the substitution board in 1974 to expedite player changes. Earlier in his career as a match director, he initiated the use of yellow flags for assistant referees and popularized the black jacket - a fashion trend that has since faded. Aston's innovations have indelibly shaped the world of football, and as we kick off a new season, let's remember the figures who have crafted the game we love.