Isao Okano had all the pressure in the world on him, as did all Japanese representatives of the judo team. They simply could not lose on their home turf, in the Budokan. But Okano, competing in the 80kg weightclass, made it all look easy. The 3rd dan form Chuo University swept through the competition. And in his semi-final bout against Frenchman Lionel Grossain, Okano wasn’t feeling the pressure – he was applying it.

Watch the above video. The chilling action starts from the 35 second mark and ends very quickly after that. Okano sends Grossain down with a right leg kick. As they hit the mat, Okano spins around and gets on top of Grossain, who is kneeling, with his head facing the mat. Grossain pushes upwards, sending Okano off, his body twisting so that his body is awkwardly facing upwards, and it appears the Frenchman has an advantage, his right arm pushing down on Okano’s chest.

But while Okano’s body is spinning, his right hand has solidly gripped the back collar of Grossain’s judogi. As the two middleweight judoka twist and turn on the mat, Okano has turned Grossain’s collar into a vise. As Okano twists away from Grossain to lift himself off the mat, Grossain’s collar puts tremendous pressure on the left side of his neck. In an instant, the pressure to Grossain’s cartoid artery restricts blood and thus oxygen to his brain, rendering him unconscious.

American Jim Bregman, who won bronze in that middle-weight competition, witnessed this match. “Grossain was very tough,” he told me. “Grossain was on top of Okano trying to hold him down, and Okano reached his hand across grabbed his gi, and put Grossain out. He’s stone cold out. With Okano’s skill and mat work, he choked him out.”

Okano had just advanced to the gold medal round, but the more immediate need was to get Grossain conscious again. Fortunately, Grossain was quickly revived by Okano, likely relieving every in the Budokan.

Okano executed a judo technique called okuri eri jime, which is the employment of the judogi in placing pressure on the neck. You can see Okano in this training video, showing very clearly how to execute this powerful technique.

Okano would go on to win the World Judo Championships in his division in 1965. More amazingly, he won the All-Japan Judo Championships in 1967 and 1969, while coming in second in 1968, a tournament that does differentiate by weight. In other words, he had to beat much larger judoka. At 80 kg, Okano (and Shinobu Sekine) is the lightest ever to win the All-Japan Judo Championships.