ST. LOUIS -- It was a most unusual error on a baseball field.A skydiver parachuting in before a summer league game accidentally kicked shortstop Mattingly Romanin in the face, knocking him to the ground and, it turns out, ending his season. The 20-year-old Mattingly said Wednesday he had a concussion and was trying to take the bizarre mishap in stride."Obviously I was a little upset and kind of frustrated about how the whole situation developed," he said. "It was a freak accident. It happens. There's nothing really I can do, I've just got to move on and make sure I'm healthy and ready to play."