European champion Dzhamal Otarsultanov won Russia's fourth wrestling gold of London 2012 with a dramatic victory in the men's 55kg freestyle.
The 25-year-old beat Georgia's Vladimer Khinchegashvili two rounds to nil.
Otarsultanov won a leg grapple in the first period, and Khinchegashvili narrowly failed to win the second round right on the bell, losing 1-0 4-3.
Shinichi Yumoto of Japan and North Korea's Yang Kyong Il claimed the two bronze medals.
Yumoto's twin brother Kenichi won Olympic bronze in the 60kg category in Beijing four years ago.
Otarsultanov had never wrestled in a senior world championships before he came to London.
He looked to be cruising to victory in the second period against Khinchegashvili, only for the Georgian to throw his opponent in the final seconds with the score at 3-3.
However, the referee ruled the move did not deserve a point and Otarsultanov, awarded a point instead, claimed victory amid boos from the Georgians in the crowd.
Russia had already earned two Greco-Roman wrestling gold medals at London 2012, with
Roman Vlasov winning at 74kg
Alan Khugaev at 84kg.
Their other freestyle gold was won by
Natalia Vorobieva in the women's 72kg category.