 Originally the JSL consisted of a single division only, but in 1972 a Second Division was added.Clubs could join in by winning the All Japan Senior Football Championship cup competition and then winning a promotion/relegation series against the bottom teams in the JSL.From 1973 to 1980, both the champions and runners-up of the Second Division had to play the promotion/relegation series against the First Division's bottom clubs; afterwards and until 1984, only the runners-up had to play the series.