A good friend and teammate of my son with a great arm never got to throw a ball past his junior year of high school. At that time he was throwing 91 mph but starting to miss time due to a variety of shoulder and back problems. The problems with him started years before when he was the "go to" guy in every club ball tournament or Little League game. Those coaches mean well and donate a lot of time and energy. But when it comes to crunch time their competitive instincts take over and they just want to win. And the way to win is put the big guy on the mound and throw him until he drops. If you have a son with a good arm who is playing club or little league I give you an honest warning: If you don't intervene in situations where your son should not be throwing, you could be ruining his chances of playing college ball or if he's really exceptional, pro. There's no telling how many talents were cut short with shoulder or elbow injuries. If your kid is in the situation now, you could make a difference but you kind of have to be the "asshole Dad" to do it. Be an asshole, tell the coach, "No he just threw a hundred pitches 2 days ago he is not ready". When your son gets a scholarship to play college ball, he'll thank you.