In 1914, Brews turned professional. He worked as the club professional at Minchinhampton Golf Club in Gloucestershire. In the mid-1920s, he emigrated to South Africa. He won the South African Open eight times between 1925 and 1952, when he became the tournament's oldest-ever champion aged 53. He also won the South African PGA Championship six times, and many provincial opens. His brother Jock Brews also won the South African Open four times.
He enjoyed considerable success outside of South Africa. In 1934, probably his finest year, he finished second in the British Open to Henry Cotton, and won both the French Open and Dutch Open championships. He would retain both of those titles in 1935.
