High Quality Content by WIKIPEDIA articles! The 1919 World Series matched the American League champion Chicago White Sox against the National League champion Cincinnati Reds. Although most World Series have been of the best-of-seven format, the 1919 World Series was a best-of-nine series (along with 1903, 1920, and 1921). Baseball decided to try the best-of-nine format partly to increase popularity of the sport and partly to generate more revenue.