Posted By:
davidcyclebackRule of thumb: First baseball card depicting the player as a Major Leaguer (or where he is a major leaguer).
In common baseball terminology, 'rookie' means first year as a Major League player, not Minor Leaguer, college or high school player.
Mark McGwire's 1984 Topps Olympic card is not his rookie card, as he is not depicted as a Major Leaguer and had not yet played in the Major Leagues. Similarly, the Baltimore News Babe Ruth is not Ruth's rookie card.
The definition of rookie is not a definition or value, rarity, desirability. Rookies are often sought after due to their rookie-ness. However, that Mantle's 1952 Topps is more valuable than his rookie card, illustrates that the rookie card is not always the 'best.'
Collect what you want. If you think the Baltimore News is Ruth's best card, that's great. If you think defining a card as a 'rookie card' is dumb, that's fine.
If you want to define a rookie card as the one from the player's rookie year (first year as a MLB player), that is a fair definition. However, many players would not have a rookie card. Many HOFer football players would have no rookie card. I don't believe Roger Staubach or Joe Montana would have rookie cards.