Following the 1986 season, the club replaced Hirooka with Masaaki Mori, who was able to sustain the team's prolonged success. Mori won eight league championships, between 1986 and 1988 and 1990–1994, and six Japan Series championships in his nine-year managing career, winning the Japan Series in 1986, 1987, 1988, 1990, 1991, and 1992.
