Photo: Office of the Governor of Massachusetts, Public domain — Source
American tennis player and pioneer for gender equality in sports who won 39 Grand Slam titles across singles, doubles, and mixed doubles. She is best known for defeating Bobby Riggs in the 1973 'Battle of the Sexes' match, watched by an estimated 90 million viewers worldwide. She founded the Women's Tennis Association (WTA) and fought successfully for equal prize money at the US Open. She also founded the Women's Sports Foundation. An early advocate for LGBTQ+ rights in sports, she was awarded the Presidential Medal of Freedom in 2009. The home of the US Open is named after her.
Source: Billie Jean King Official Site