Top 3 — Most Important

[Misunderestimated]

Harry Wright
Ruth
Jackie
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Ruth and Jackie are undeniable....I also thought about Spalding and Ward instead of Harry Wright for the 19th Century slot..... Others who come to mind are Rube Foster (the father of the first Negro Leagues and a great pitcher), Cal Ripken (for reinvigorating the game post-strike), John McGraw for strategic impact, Ned Hanlon for his "managerial tree" (which included McGraw !); Amos Rusie and Bob Gibson both semed to bring about rule changes; Ted Williams (not just for his singular excellence as a hitter but for speaking out for including the Negro Leaguers in the HOF); Roberto Clemente; and, projecting out a little, I think Ichiro Suzuki will be considered very important.

Other players were truly great but I'm not sure how "important" they really were: Nichols, Young, Cobb, Speaker, Gehrig, Hornsby, Ott, DiMaggio, Mantle, McGwire, Barry Bonds, Pujols and ARod...