As a winger, Germishuys was known for his speed and agility. His international rugby debut was on 22 June 1974 for the Springboks against the British Lions. He also played against the All Blacks in 1976 and the Lions in 1980. In 1981, he participated in the infamous South Africa rugby team tour of New Zealand. His last cap was on 20 September 1981 against the United States rugby team. He also played in the Currie Cup competition for the provincial teams of the Orange Free State from 1974-1977 and the Transvaal from 1980-1981.