JEF United Ichihara Chiba
During the 2012 J.League Division 2 season, Oita Trinita finished in sixth place, qualifying for the promotion playoffs in the first year of its introduction in Japan's second flight as the club had also paid back all its emergency loans that October. Despite being the lowest seed, Oita Trinita defeated Kyoto Sanga F.C. 4–0 in the semi-final and JEF United Ichihara Chiba 1–0 in the final, earning promotion to 2013 J.League Division 1, returning to the top flight after a 5-year absence This time, however, their top flight stay lasted only one season. In 2015 they were further relegated to J3 League after losing in the promotion playoffs to Machida Zelvia on December 6, becoming the first major trophy winner to be relegated to the third tier. The club immediately gained promotion back to J2 League by winning the J3 League title in 2016.