Yokohama FC, the club created by fans of former J. League top-flight team Yokohama Flugels, booked a spot in the first division for 2020 with a 2-0 win at home over Ehime FC on Sunday.
The win on the final day of the J2 season earned Yokohama FC second place and its second J1 season and first since 2007, when it finished 18th and earned a quick drop to the second division.
Yusuke Minagawa converted a penalty kick in the 32nd minute and Kosuke Saito scored Yokohama FC's other goal in the 52nd minute.
Elsewhere, J2 champions Kashiwa Reysol completed their season in the second tier with a 13-1 thumping of visiting Kyoto Sanga, with Kenyan striker Olunga scoring eight goals.
Yokohama FC and Reysol will replace the bottom two J1 teams. The four clubs finishing third to sixth in J2 — Omiya Ardija, Tokushima Vortis, Ventforet Kofu and Montedio Yamagata — will compete for a chance to take part in a relegation-promotion playoff game against the J1 team finishing 16th.