South Korea's Kim Hyeon-woo won gold in the -66kg Greco-Roman wrestling competition, beating Hungarian Tamas Lorincz in the final.
Kim, 24, defeated Lorincz in two rounds with scores of 1-0 2-0 to secure a first wrestling gold medal of the London Olympics for South Korea.
Colin Bryce, former Great Britain Olympic bobsledder:
"Gold makes those thousands of hours of training worth it for Kim. He is only 24 and I am sure we will see him in Rio to defend his title."
France's Steeve Guenot, who was beaten by Kim in the quarter-finals, and Manuchar Tskhadaia won bronze medals.
Guenot was the Olympic champion in Beijing four years ago.
Kim has only been a professional wrestler for two years, but won the Asian Championship on his debut.
He was in complete control against Lorincz, using his strength to successfully defend a par terre in the first period before lifting his opponent in the second to seal the win.
World champion and pre-Olympic favourite Saeid Morad Abdvali had suffered a surprise defeat to Guenot in the quarter-finals.
It was the Iranian's first loss in 20 months, with his last defeat in a major competition coming in the third round of the 2010 World Championship.