If you are looking at fielding statistics, it could stand for 'Assists'. If you are looking at yearly statistics and AS is shown as the far right at the end of the line, it could stand for 'All Star'.
GBL in Baseball means "Golden Baseball League
major league baseball
a stand up double in baseball is when the batter hits a double and doesn't have to slide at second.
Runs
Error
Shortstop
OF stands for outfield.
national league baseball
Wealthy As Rich
Catcher's Interference
at bats
Game.