Their greatest success was winning the French Open 1927. In the ladies' final she beat Irene Peacock from South Africa in straight sets 6-2, 6-4. She was the first ( and to date only ) Dutch tennis player ever to win a Grand Slam tournament.
She also won the bronze medal in the mixed doubles with her partner Hendrik Timmer at the Summer Olympic Games in 1924 in Paris. In 1929, she won even with the Spaniard Lili Alvarez the doubles title in Paris against the South Africans Bobby Heine and Alida Neave 7:5, 6:3.
However, it was also successful in other disciplines, was Dutch golf champion and played for the national hockey team.