Has your son asked him about it? I know it is very tough at that age but if your son can handle it that is the best way. And that coach seems like an ass. 11-1 is the perfect time to put someone in. And in no shape or form should winning take a priority over development at 10 years old. That whole league needs to look at their priorities if they are waiting until the last game for that. Edit: and the worst coaches aren't necessarily the ones doing it to give their kids an advantage but the ones doing it for their own ego.