Why did the number of Black players in professional baseball decline after 1887?

The decline of Black players in professional baseball after 1887 was not the result of an official rule, but rather the emergence of a "gentlemen’s agreement" among team owners and league officials to exclude African Americans from "Organized Baseball".123

During 1887, racial tensions in the sport intensified. Several incidents signaled this shift, including:

• Team Mutinies: Players on the Syracuse Stars refused to be photographed with their Black teammate, Robert Higgins.23
• Exclusionary Demands: Prominent figures like Cap Anson insisted that Black players be kept out of exhibition games against major league teams.23
• Refusal to Compete: Some teams, such as the St. Louis Browns, explicitly refused to play against Black clubs, stating they would only compete against white teams.23

In response to these pressures, the International League’s board of directors directed its secretary to stop approving contracts for Black players midseason. While Black athletes remained in the minor leagues for a few years, their numbers steadily dwindled as discriminatory customs and, eventually, broader societal segregation laws like Plessy v. Ferguson solidified the color barrier.23