It is definitely UFO Senshi Dai Apolon. The crystal falling into the guy on the football field during the rain, the old man who explains stuff, the "growing into the football robot" thing. I didn't see the stuff where the old man explodes the 8 ball though. Maybe it is in a later ep? Either way I am sure this is it. Thanks for the help. Now if only I knew where to get this in English or Japanese subbed.