Maybe he just had a sore throat from yelling so much. I think that might be it cause he looks way too old to be going through puberty and there was no evidence of his balls dropping.
OR maybe he tried some kind of experimental serum for his team to make himself younger. But it only made his voice younger. Soon he'll be shouting at his team in the voice of a child and no one will take him seriously. He'll have to quit the world of sports, only to wind up working at a burger place on the mike because it will be the only place no one will notice...so so sad.