Baseball rubbing mud

Common card · No. 280191

Baseball rubbing mud is mud that has been gathered or prepared for the purpose of rubbing it on a baseball. Balls made for the sport of baseball have a somewhat slick and glossy surface when they are newly manufactured, so before they are used in official league games, they are rubbed down with mud to reduce their slickness and give pitchers a firmer grip and better control. Major League Baseball rules require every "pearl", or brand-new baseball, to be rubbed with mud for at least 30 seconds on game day until it achieves the desired texture and off-white color. The effects of adding a substance to the ball have called the attention of physicists over the years.

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