In 1973, Billie Jean King played one of the most important tennis matches ever: The Battle of the Sexes. That day, she changed the male-dominated tennis establishment in a pair of blue adidas. For the 45th anniversary, we could have re-released her shoe. But that's not how BJK would do it. She prefers to change things. So we did just that, changing the most iconic Adidas models into blue BJKs. And at the U.S. Open we invited everyone to BJK their shoes– no matter what brand. For the first time ever, a brand utilized other brands to launch a shoe.