I think the nearest thing we have to competitive baseball over here is cricket - now that IS a boring sport!

But, my father and brother are mad on it; my brother actually plays at county level and my dad coaches youth teams. It is a huge part of their lives and they talk about it all the time. It drives my mother and I nuts. I can't usually stand more than 10 minutes of it!

That being said, I would endure the hours of being bored out my skull, if it meant something to the family, to the group, business team, whatever. Team building's what you make of it, I guess, and not going appears antisocial, no matter how well you and your boss get along I'm afraid. Though, I'm sure he knows there are no hard feelings.

Like others have suggested, I think a few hints at what you'd like to do are needed! Since you get along so well with your boss I'm sure he'll endeavour to find something you can all enjoy.