OYO’s 2012 release of Generation One Minifigures is the first series that reflects a full complement of MLB teams. It is noted by the “Generation One, Limited Edition” verbiage at the top of the packaging.
Not all of the G1 players from 2012, are the first OYOs for that player, as some players were produced in 2011 as a “preview” set of G1.
This checklist includes all of the regular versions of these players.
Happy Hunting for these early OYO minifigures in MLB, and MILB!