Dae-Nam Song won
South Korea's second judo gold medal
and third in all by beating Cuba's Asley Gonzalez in the men's -90kg final.
Gonzalez, who had three ippons en route to the final, was the more proactive during the five-minute bout.
However, Song won the contest on a golden score thanks to a decisive waza-ari 10 seconds into extra-time.
Great Britain's three-time Olympian
Winston Gordon was beaten in the second round by Russia's Kirill Denisov.
The two bronze medals were won by Ilias Iliadis of Greece, who beat Brazilian veteran Tiago Camilo, and Japan's Masashi Nishiyama, who overcame Denisov.
Iliadis's medal was his country's first of the Games, while Nishiyama's made it six judo medals so far for traditional powerhouse Japan.
Gordon beat Canada's Alexandre Emond in his first round contest to become only the second British judoka to win a bout in the five days of competition so far.
Gordon, who was given a rousing reception at the ExCeL Centre, won by ippon, delivering a perfect Tai-otoshi body drop on the world number 14. However, the Londoner lost to Denisov in the next round.