Away from the courts at Wimbledon last night, Billie Jean King and a group of women’s tennis pioneers attended a London premiere for “The Battle of the Sexes,” a new doc on King’s 1973 match against Bobby Riggs. At the Leicester Square screening with King were 12-time Grand Slam champ Rosie Casals, Aussie greats Judy Dalton and Evonne Goolagong, World Team Tennis commissioner and King’s partner Ilana Kloss, Dutch former pro Betty Stöve and French player Françoise Dürr. Also there were Oscar winner Danny Boyle and director Simon Curtis. “Billie Jean introduced the film, to a standing ovation,” said a spy. “She thanked the players in the crowd” who helped her campaign for equal pay for women in the sport. “I can’t be happier or prouder of the current women players today,” added King, who will be the subject of another upcoming doc for American Masters featuring Elton John, Chris Evert, Venus Williams and Gloria Steinem. King will celebrate her 70th birthday this fall with a bash in Las Vegas, where we hear John will play.