Before turning professional, Kloss won the juniors singles title at
Wimbledon in 1972. She won the SA doubles title with
Linky Boshoff in 1973, 1975, and 1977. She also played in the
Maccabiah Games in Israel, winning gold medals in the singles, women's doubles (with Helen Weiner defeating silver medalists
Vicki Berner and Pam Gullish of Canada in the finals), and the mixed doubles in the
1973 Maccabiah Games. She also won a silver medal in mixed doubles in the
1977 Maccabiah Games, losing to
Peter Rennert and
Stacy Margolin. In 1974, she won the
US Open juniors singles title. In 1973, she won the title in
Cincinnati with Pat Walkden, defeating
Evonne Goolagong and
Janet Young in the final. Kloss was ranked No. 1 in the world in doubles and No. 19 in singles in 1976. That year, she won doubles titles at the US Open, the
Italian Open, the US Clay Courts, the
German Open, the British Hard Courts Championship, and
Hilton Head, as well as the mixed doubles title at the
French Open.
Federation Cup From 1973 until 1977, Kloss was a member of the
South African team that competed in the
Federation Cup. She compiled a 12–5 win–loss record.
World Team Tennis Kloss joined the
San Francisco Golden Gaters WTT team in 1974, and reached the WTT Finals with the team in 1975. She left the Golden Gaters prior to the 1976 season to team in order to fully participate in
clay-court tournaments in
Europe which conflicted with the WTT schedule. Kloss returned to the Golden Gaters for the 1978 season. In 1983, she coached the Chicago Fyre to a WTT Championship and was named Coach of the Year. In 1985, Kloss was a player and coach for the Miami Beach Breakers, and became vice-president of WTT in 1987 and executive director in 1991. Since 2001, she has been the chief executive officer and commissioner of World Team Tennis. ==Grand Slam tournament finals==