Kids, learn from the pros -- hitting yourself in the head with a baseball bat is a bad thing. Even if you are wearing a helmet.
Orioles second baseman Brian Robinson missed the last six games of the season with concussion-like symptoms.
"I don't know 100 percent sure [what caused the concussion], but it was Monday night. In frustration, I whacked myself on the head with my bat in the ninth. I had my helmet on," Roberts told Brittany Ghiroli of MLB.com . "It's something I've done a million times, but I can't tell you for sure if that was it. But that's the only thing that I can point to because that night and the next morning, I just didn't feel good."
Roberts said he's had a "lack of balance" and headaches since Monday.
-- C. Trent Rosecrans
For more baseball news, rumors and analysis, follow @cbssportsmlb on Twitter or subscribe to the RSS feed .