there was a kid like this when my little brothers played. He had some pituitary disease that made him age fast. Dude had a full beard and was muscular as hell in the 6th grade. They had a weight limit, so he couldn't run the ball, but he would steal it from ball carriers, and flatten everybody like that. On defense he would spear the hell out of everybody. He actually had speed though. Funny thing was, he never got any taller or bigger and looked like a babyface in high school. Coach put him on varsity when I was a senior, but by then he was a little pip squeak.