Otto Blom was Dutch singles champion in 1909-11, and won national titles in doubles in 1909 and 1912, and in mixed in 1906 and 1911. He reached the fourth round at Wimbledon in 1910, losing in the first round in 1909. He retired after the 1912 Dutch Championship, when he lost to 16-year-old Arthur Diemer Kool in the final, which annoyed him so much that he quit the sport. Blom’s son later married Kool’s daughter, and two of their grandchildren, Otto and Nora Blom, reached the national level in Dutch tennis.