She won a doubles match partnering Dorothy Bundy and helped the U.S.
team to a 5–2 victory.Arnold was ranked in the U.S.
Top 10 every year between 1939 and 1947.
Her highest ranking came in 1942 and 1944 when she was ranked No.
5 in both years.At the 1948 French Championships, she paired with future International Tennis Hall of Fame inductee Shirley Fry to reach the doubles finals.
She also played at the Wimbledon Championships that year and reached the third round in the singles and doubles and the quarterfinal in the mixed doubles event.At the Tri-State Tennis Tournament (now Cincinnati Masters), she reached five finals, winning three doubles titles: 1940, 1944 and 1946.
She also was a singles finalist in 1941 (losing to Pauline Betz), and was a doubles finalist in 1945 (with Fry).
To win her doubles titles in Cincinnati, she paired with Alice Marble in 1940, with Dorothy Bundy in 1944, and with Fry in 1946.