Charlie-O the Mule was purchased from Harold Sloan a small town farmer and muleskinner from Osborn, Missouri.
Use of an elephant to symbolize the Athletics dates from the early years of the franchise, when a group of Philadelphia businessmen headed by industrialist Benjamin Shibe became the team's first owners.
When asked to comment, John McGraw, manager of the New York Giants of the rival National League said something to the effect that Shibe had bought himself a "white elephant."
Finley took the sorrel 15 hands (60 inches, 152 cm) mule around the country, walking him into cocktail parties and hotel lobbies, and on one occasion even into the press room after a large feeding to annoy reporters.
When the Athletics left Kansas City after the 1967 season, there was debate about whether Charlie-O should stay but Finley declared he was a gift and took him with him to Oakland in 1968.