This is definitely a standard feature of Asperger's. And a hard one to deal with.
Some thoughts:
--Soccer is an extremely hard sport for an overexcitable kid. It's overstimulating, the whole game keeps changing direction around him (disorienting), and he is getting inadvertently kicked a lot. All that increases the likelihood of coping problems.
-- Losing at board games is an easier first skill because it doesn't have the physical and sensory overkill. Still, it takes practice. We started here.
--In sports we focused first on fitness and individual sports (swimming) and then turned to things like golf, which is a good one because if you lose you have only yourself to blame. After he had some skills in controlling his own frustration when he missed a shot, we taught him to compliment others' shots when they were good, then started golf play dates with other kids.
--We also let him watch us lose at both board games and sports and model the process for him; then we let him rate our performance as good or poor losers.
--Core skills include: knowing it's not the end of the world to lose (only experience teaches this); valuing others' achievements and complimenting them; being able to keep one's perfectionism about one's own contribution under control. We look for situations where we can practice each of these components separately, as well as together in a game context.
HTH,
DeeDee
