G
- "The Gambler" = Kenny Rogers, American starting pitcher, so nicknamed after the hit song recorded by the country singer of the same name.
- "Gator" =
- Mike Greenwell, American left fielder
- Ron Guidry, American starting pitcher
- "Gee" = Gerald Walker, United States baseball player
- "The Georgia Peach" = Ty Cobb, United States baseball player
- "Generation K" = three pitching prospects in the New York Mets organization, Paul Wilson, Bill Pulsipher, and Jason Isringhausen
- "Germany" = Herman A. Schaefer, United States baseball player
- "Godzilla" = Hideki Matsui, Japanese left fielder
- "Gonzo" = Luis Gonzalez, American outfielder
- "Goose" =
- Leon Goslin, United States baseball player
- Rich Gossage, American closer
- "Gorgeous George" = George Sisler, American first baseman
- "Le Grand Orange" (French, "Big Red") = Daniel Staub, American outfielder (for his red hair)
- "The Great One" = Roberto Clemente, Hall of Fame Puerto Rican baseball player
- "The Greek God of Walks" = Kevin Youkilis, American first baseman and third baseman
- "The Grey Eagle" = Tris Speaker, American outfielder and manager
- "El Guapo" (Spanish, "The Handsome One") = Rich Garcés, Venezuelan baseball player
Read more about this topic: List Of Baseball Player Nicknames