After the 1949 season, the JBL team owners reorganized into the NPB; Daiei Stars owner Masaichi Nagata promoted a two-league system, which became the Pacific League (initially called the Taiheiyo Baseball Union) and the Central League.
Four JBL teams formed the basis of the Central League: the Chunichi Dragons, the Hanshin Tigers, the Yomiuri Giants, and the Shochiku Robins (formerly the Taiyō Robins).