The legend of Mabel Esmonde Cahill never fully developed and she remains one of the International Tennis Hall of Fame’s great mysteries. Her tennis history is thin, albeit prosperous. She was born in County Kilkenny, Ireland and established residence in New York. In 1891 she became the first foreign player to win one of the major championships, defeating Ellen Roosevelt 6-4, 6-1, 4-6, 6-3 to win the U.S. National Women’s Singles Championship. She successfully defended her title the following year, defeating Elisabeth Moore in a hard fought, five-set final, 5-7, 6-3, 6-4, 4-6, 6-2. Both years saw Cahill win U.S. National Women’s Doubles Championships. In 1891 she teamed with Emma Leavitt-Morgan to hand the Roosevelt sisters, Ellen and Grace, a 2-6, 8-6, 6-4 defeat. In 1892 she paired with Adeline McKinlay and the pair downed Mrs. A.H. Harris and Amy R. Williams easily, 6-1, 6-3. Cahill paired with Clarence Hobart to win the mixed doubles title in 1892, over Moore and Rodmond Beach, 6-1, 6-3.
In 1893, Cahill elected not to defend her U.S. crown, and did not compete again on the international level, leaving her legacy as one of 25 women in history to win back-to-back U.S. singles championships.