In the fall of 1975, Joan became the first full-time women’s golf coach at the University of Oklahoma. With no scholarships, and a very young team, Joan was facing a huge challenge. In just the seventh event of Joan’s coaching career, the OU women won their first tournament. Later that year, OU placed third in their first Big 8 Championship.
In 1978 OU won the first of two Big 8 Championships under Joan’s leadership. After just 25 events, OU went from no women’s golf program at all, to winning the Big 8 Championship. OU won 9 times during Joan’s coaching career. Joan had an individual or team qualify for the AIAW National Championship every year she coached. Her teams never finished lower than 3rd in Big 8 Conference Championship play. Joan brought another Big 8 championship to Norman in 1981.
Joan conducted workshops locally, nationally, and in Mexico, and was recognized for her teaching ability. She was a member of the USGA and the LPGA Teaching Division.
In 1979, Joan was diagnosed with breast cancer. In 1982, for health reasons, Joan left coaching to become the OU Athletic Department Promotions Coordinator. Finally, in September 1984, Joan had to resign. Five months later she died, at the age of 53.
In 1986, the NCAA Convention adopted a resolution commemorating Joan’s distinguished service to athletics. As a tribute to her accomplishments, her children established a memorial scholarship fund at OU in her name. She also has an award named after her; The Blumenthal Award is given annually to the women’s golf team’s most valuable player.