World Cup Football Ball

Although Gaelic football has been played with a round ball since first organized in 1887, balls made by the Irish sports company O'Neills have been used sometime since the company was founded in 1918 and are recognized as the official ball to be played with, although it is now permitted to use the Gaelic ball manufactured by the Irish sports company Gaelic Gear.
• Rugby football
Richard Lindon and Bernardo Solano started making balls for Rugby school out of hand stitched, four-panel, leather casings and pigs’ bladders. The rugby ball's distinctive shape is supposedly due to the pig’s bladder, although early balls were more plum-shaped than oval. The balls varied in size in the beginning depending upon how large the pig’s bladder was.
Until 1870, rugby was played with a near spherical ball with an inner-tube made of a pig's bladder. In 1870 Richard Lindon introduced rubber inner-tubes and because of the pliability of rubber the shape gradually changed from a sphere to an egg. In 1892 the RFU endorsed ovalness as the compulsory shape. The gradual flattening of the ball continued over the years.