mental coaching of youth

Question
I am the father of a seven y/o boy, and I am the assistant coach of the team he plays for. The league (PONY) he is in, is  player pitch, ages 7-8. My son is one of the better pitchers in the league, however he has a problem controlling his emotions when things don't go well. When he gets upset on the mound, he quickly goes from very good to very bad. I've explained to him that getting upset does not work. I've also been careful not to get on him for shortcomings, rather it's pitching, hitting, etc. He seems to understand what I'm saying, but the problem persists. Is this common? Is this probably something I've created? Your advice would be greatly appreciated.

Answer
Santi,first of all I must say that I think 7-8 is way to young for a kid to be pitching.Secondly,if it was me I would tell him if he cannot controll his temper on the mound then he will not be pitching.You have to make sure he is not devolping a BAD ATTITUDE.Try showing him how the guys in the playoffs are acting on the mound.Keeping thier head when things dont go thier way.Also what I do with my son since I was coaching him was I would tell him about things he needed to correct during the game but after the game on the way home I never bring up anything he did unless he brings it up.Then I tried to never beat a dead hourse.If you know what I mean.Please understand this, If you dont tell your son about the mestakes he is making how will he correct them in order to get better? You get better by correcting those shortcomings not ignoring them.