John O'Brien was born on Friday, July 13, 1866, in Saint John, New Brunswick, Canada. O'Brien was 24 years old when he broke into the big leagues on April 22, 1891, with the Brooklyn Bridegrooms.
John “Chewing Gum” O’Brien
In the 1800's there were not many baseball players who chewed gum in the dugout or during the games. John O'Brien was one of the first ones to do so, which explains his nickname.
