Walt Whitman was a baseball fan
"I believe in all that--in baseball, in picnics, in freedom."
Walt Whitman, June 5, 1888.
“I like your interest in sports ball, chiefest of all base-ball particularly: base-ball is our game: the American game: I connect it with our national character. Sports take people out of doors, get them filled with oxygen generate some of the brutal customs (so-called brutal customs) which, after all, tend to habituate people to a necessary physical stoicism. We are some ways a dyspeptic, nervous set: anything which will repair such losses may be regarded as a blessing to the race. We want to go out and howl, swear, run, jump, wrestle, even fight, if only by so doing we may improve the guts of the people: the guts, vile as guts are, divine as guts are!”
Walt Whitman, September 1888