As Manager Alexander J. McKinnon (August 14, 1856 – July 24, 1887) was an American Major League Baseball first baseman from Boston, Massachusetts.

[2] He decided to quit playing baseball after the season and moved west to engage in business interests.

On March 5, 1883, he was re-instated during a special session of the National League, and signed with the Philadelphia Quakers.

[1] The 1887 season began with McKinnon improving his hitting and fielding, likely becoming one of the better first basemen in the National League,[1] when he contracted typhoid pneumonia and subsequently died in Charlestown, Massachusetts at the age of 30.

[6] Pittsburgh wore a black crêpe on their uniforms for the rest of the season to honor Alex.