France's Suzanne Lenglen was pretty much invincible in women's tennis in the 1920s, losing only one match of significance in singles from 1914 through 1926. She ruled the sport when the major tournaments were amatuer events only. This photo of Lenglen was taken at the 1920 Olympic Games in Antwerp, Belgium. Considered a sex symbol in her heyday, Lenglen turned professional after 1926 and played a series of exhibition matches in the United States that didn't draw very good crowds because Lenglen so outclassed her competition. She died of leukemia in 1938 when she was only 39 years old.