Curving
A unique aspect of Trac Ball is the ease at which curves can be attained. The grooves in the racquet along with the striations on the ball provide a great deal of spin which allows players to throw deep curveballs with little effort.
Holding the racquet perpendicular to the ground and throwing forward will cause the ball to spin backwards towards the thrower. This usually causes a higher flight than intended when aiming directly at the catcher. Throw distance is extended by ball spin, but the curve is otherwise unnoticeable.
A more dramatic curving effect can be caused by holding the racquet parallel to the ground. The ball will curve back towards the catcher if, for instance, the racquet is held out to the right by a right-handed person and the ball is aimed approximately 30 degrees to the left of the catcher or more (depending on the velocity of the throw).
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