1921 U.S. National Championships – Women's Singles
defeated Mary Browne 4–6, 6–4, 6–2 in the final to win the Women's Singles tennis title at the 1921 U.S. National Championships. The event was held at the West Side Tennis Club, Forest Hills, New York City, from August 15 through August 20, 1921. It was Mallory's sixth U.S. National singles title.Draw
