It's time to talk of mice and McCaw. While that Richie won't be playing in 2019 edition of the Rugby World Cup soon to be held in Japan, it is time to wonder which ball the new Richie (Mo'unga) will be kicking off with in the final on November 2.

This will be the seventh rugby world cup for which Gilbert have supplied the official match ball, and they continue to make changes to improve handling and aerodynamics. Gilbert have been producing footballs since 1823, and it is said that the ball picked up by William Webb Ellis all those years ago was a Gilbert.

While Adidas have sought to improve their world cup soccer balls by reducing the number of seams, getting down now to a six-piece ball, rugby balls have been settled in their four-piece configuration for many decades. It's even defined as such within the Laws of Rugby.

So, where then have the changes been made?

After problems with the aerodynamics of the ball used in the 2003 tournament, the shape of the 'pimples' on the surface of the ball were changed from round to star shaped to improve handling and kickability for the 2007 tournament. Remarkably, Gilbert (and their new owners, Grays International) don't seek protection for very much of their innovation, but in this case they did, which was published as WO2006/061608.

The next development was for the 2011 tournament where a new valve was produced, which distributed weight along the seams of the ball to improve rotational stability and accuracy.

Both these features were retained for the 2015 world cup ball, and most of the improvement appears to have been in the polymers and laminations of the synthetic cover material.

Moving forward to the latest ball to be used in 2019, Gilbert have made further improvements to the pimples, making them 'dual height', and altering their distribution across the surface. This needed to be done without increasing the actual height of the pimples as it would have affected the aerodynamics, but as there doesn't appear to be any patent protection and hence publication of the details, all I can say is they claim to have produced a ball with the largest total surface area of any international match ball.

These changes seem to be getting more and more infinitesimal and highly technical, which someone has suggested is creating a rugby ball that is close to perfection, so it will be interesting what Gilbert come up with as we approach 2023.

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