(Updates with quotes)
LONDON, July 30 (Reuters) - Mansur Isaev won Russia's second judo gold in London in the space of three days on Monday, putting their success on the mat down to an overhaul of the sport in his country
Fourth seed Isaev, 25, triumphed in the men's -73kg category, coming out on top in a fast and furious final fight with Japan's Riki Nakaya.
"I was very focused, and extremely focused inside. I knew what I wanted, I knew where I was going and I knew what today meant," he told reporters.
"The Olympic medal is a combination of every effort I have made in the last four years, physical and psychological preparation and my coach told me you are at your peak."
He thoroughly deserved gold after beating Nakaya, the world number two, and earlier overcoming South Korea's Wang Ki-Chun, the world number one and silver medal winner in Beijing who had bettered him in their previous six meetings.
"I wanted to prove not only to him but myself that I'm the best in the world," Isaev said.
His win emulated the success of countryman Arsen Galstyan on Saturday who had earned Russia's first judo gold since the collapse of the Soviet Union.
Isaev put the success down to a new structure for Russian judo under Italian Ezio Gamba, Olympic champion himself in 1980, which means they train together and compete in all tournaments across the world to get more experience.
"He told us we would train and work 300 days a year and that's what happened. He is just a great man," Isaev said.
Mongolia's Nyam-Ochir Sainjargal took bronze by beating Dutchman Dex Elmont whose brother Guillaume will compete in the -81 kg section on Tuesday.
It means Mongolia have now won judo medals at every games since Athens in 2004.
France's Ugo Legrand defeated Wang to win the other bronze, his country's third judo bronze medal in London, and received a standing ovation from watching French President Francois Hollande, who greeted him enthusiastically after his win. (editing by Ed Osmond and Alison Wildey)