It’s been 33 years since Stan Smith retired from the game of tennis, but you’d never know it from his sneaker sales.

Smith won the U.S. Open in 1971 and Wimbledon in 1972, and was inducted into the International Tennis Hall of Fame in 1987. In 2005, TENNIS magazine ranked Smith as one of the “40 Greatest Players of the TENNIS era.” Smith was winning Grand Slams, garnering acclaim and ascending to the world’s number one ranking in the early-1970s, but it wasn’t until adidas reached out in the hopes he would become the new face—literally—of its leather tennis shoe, creating one of the greatest and most successful partnerships in sneaker history. From here, the tennis star became a truly (unlikely) fashion icon.

But to understand the origins of the Stan Smith, you have to go back to the shoe’s original name: the adidas Robert Haillet.

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