Rosenthal was born in Minneapolis, Minnesota. She attended the University of Tulsa. As an amateur she won the 1984 British Ladies Amateur and played for the United States in the 1984 Curtis Cup.
Her debut season on the LPGA Tour was 1986. She won Rookie of the Year honours. In her second season she won two tournaments, including the du Maurier Classic, which was then one of the LPGA’s Major championships. She also finished in the top ten in the other three Majors of the year, and finished fifth on the money list.
From that time onwards, however, her career followed a downwards trajectory. She failed to win again and did not make the top 100 on the money list after 1992. She last played on the LPGA Tour in 2002.