 TuS 48/99 then made its own appearance in the Gauliga earning a second-place finish in the 1936–37 season, only a single point behind division winners TSV Fortuna Düsseldorf.The following season TSV and TuS were directed by Nazi sport authorities to merge to play as TuS Duisburg 48/99.This team struggled, several times narrowly missing relegation, until another second-place result in 1942.