He won the men's doubles title with Beals Wright at the Olympic Games in St. Louis . They only made one set in the whole tournament. In singles he got the bronze medal after losing to his doubles partner. Wright and Leonard were in the same class at Harvard University , where Leonard graduated in 1903. There Leonard had led the college team as captain and won the intercollegiate double title in 1902. Its highest national ranking was 8th in 1903.
After graduating, Leonard worked in his father's textile company. In 1915 he started a brokerage firm in New York City called Moore, Leonard, & Lynch , for which he worked until his death.