William Michael Crowley (April 18, 1857 – July 14, 1891) was an American Major League Baseball player who played mainly as an outfielder from 1875 to 1885.

[3] Crowley threw out four men from the outfield during a May 1880 game with the Buffalo Bisons, and he did it again in August of that year.

The bans were thought to take aim at drunkenness, rowdy behavior and game fixing among the league's players, but all of the blacklisting was lumped under a broad category: "general dissipation and insubordination.

On June 7, 1884, while Crowley was playing for the Boston Beaneaters, Providence Grays pitcher Charlie Sweeney struck out Crowley to end the game and to set a single-game major league strikeout record (19 strikeouts).

From 1886 to 1888, Crowley appeared with four minor league teams before leaving professional baseball.