The balls used in football's biggest matches have undergone a dramatic transformation since the first tournament in Uruguay back in 1930
The history of the World Cup in many ways tells the story of the evolution of professional football itself.
That is visible in the development of the World Cup ball, which has gone from a leather-bound pig's bladder to the high-tech, synthetic spheres we see sold in stores and marketed around the world today.
The ball has also played its part in setting the course of World Cup history.
From a half-time ball change that influenced a final to the "supermarket" model despised by goalkeepers, here is Goal's history of the official World Cup football.