Abstract: A non-pressurized sport ball that simulates the resiliency, rebound, hardness and weight properties of a similar sized, inflatable sports ball. The sports ball, which can be made in different sizes and shapes, includes a hollow ball body with relatively thick sidewalls made of closed-cell foam, elastomeric resin. When cured, the sidewalls have compression and resiliency properties that enable the working action of the sidewalls to be used in place of an air bladder in an inflatable sports ball. Formed on the ball body is an entry hole in which an air escaping cap is inserted made of the same elastomeric resin material as the ball body. During use, the cap flexes within the entry hole to allow air to exit and enter the ball during use so that the internal and external air pressures are equal. Also disclosed is a method of manufacturing the sports ball using a mandrel and a suitable-shaped compression mold with an entry hole formed on one side.