Now is it RBI or RBIs? It's Runs Batted In, not Run Batted Ins. I'm not picking on you -- I had never thought about it until I got stuck on it typing out my post. I'm going to go with RsBI.
I'm not an english major but I think there are rules that deal with acronyms like that. You always hear people saying "ribbies" aka RBIs, but yeah it's sort of awkward. I like RsBI, they can start calling 'em "raspberries"