Van der Merwe began his Rugby career wat Worcester Boys' High School in 1923. The following year he went to Rondebosch High, and for two years was one of the best forwards in school Rugby. In 1927 he returned to Worcester where he has been the leading player ever since. Heavy, strong and fast, he quickly caught the eye of the selectors, and in 1928 he played for Western Province against the All Blacks.
Van der Merwe is a solid hard-working forward, who makes the most of his strengths and weight. Notwithstanding this, he is very fast and never lags behind. He is 22 years old, weighs 200 lbs., and is 5 ft 10 ins. in height.