If a large air-filled ball like a soccer ball, volleyball or basketball hits your eye with enough force it can definitely do some serious damage. The reason has to do with the physics. Doctors tell us that the deformation of the ball upon impact will allow most balls to penetrate smaller areas than would be possible with the ball at rest. At a high impact, the ball flattens and becomes more elastic so that a portion of it can protrude into a small space. If the ball is larger than the orbital opening, the forehead and the orbital rim will absorb part of the impact, but some of it will reach the eye. This is how a soccer ball or volleyball is capable of causing significant eye injury. And why you should always wear safety glasses.