IS THE BALL SPHERICAL?
A common practice to determine if the ball is spherical or has been misshapen by abuse or neglect is to spin the ball in the air two or three times and look at the spin of the ball. If the ball seems to wobble in the air, it may be misshapen and the referee should consider a different ball for the match.

SUITABLE MATERIAL?
The referee can normally determine if the material is suitable by inspecting the ball for loose panels, cuts or gashes that may injure a player or result in a defective ball in the course of play. Typically, intact commercial balls made of suitable materials. Stitched leather or synthetic covering balls are best suited for competitive matches. Some balls are made with a soft cushioned material that may gather moisture in poor weather conditions. The referee will have to consider the level of play, age of the player, and weather conditions when considering the suitability of the ball and materials of its construction.

THE BALL
Law II does not require balls to be of a particular color or material. The referee may replace the original ball with one of a different color if this makes the ball more visible. The game ball should be supplied by the home team, with several other suitable balls in reserve. When more than one game ball is provided for a match, the referee must inspect all balls to be used to ensure they meet the requirements of Law II.

PROPER PRESSURE?
There are numerous tricks used by referees to determine if the ball is properly inflated. Some referees squeeze the ball and look for a slight dimple, while others bounce the ball and look for an expected rebound height. The easiest and most accurate way is to carry a small pressure gauge and simply check the ball during your inspection. Typically, less skilled players want a soft ball, while the more aggressive and stronger players want a hard ball. The best answer is to assure that the ball is inflated within the proper pressure range using a pressure gauge.