8 yr son can't handle losing

My 8 year old son cannot handle situations where he loses.  Today at a baseball camp he was the 2nd to last in a game of pickle (coaches tag the kids as they run from base to base) out of 40.  When he was tagged out he began to cry and said it was not fair.  This seems to be a running theme as of late.  He throws a tantrum (which is not like him).  He is my sensitive first born and I know that plays into this but I don't know what tools I can teach him to handle these situations?  He cries/tantrums when he loses a lego, when his younger sister doesn't play a game correctly etc...  His answer in the camp was to cry and sit out the remainder of the day.  I have tried the "count to 10" to get him to calm himself down and even "LIG" let it go... neither is working.  I am sure maturity will help (he is a young 8) but what can I do in the meantime to help him?  Thanks!

[Kevin Kennedy, Ph.D.]

You can help him by establishing a reward system whereby he earns access to some favored activity or privilege by managing disappointments in better fashion. Such a system will build his motivation to exercise improved self control.