Dagvadorj’s office in Ulaanbaatar is large but understated. Of course he has a portrait of Genghis Khan on the wall. The desk is big, too, but so is the man who greets a visitor, wearing Air Jordan sandals and a rumpled tailored suit, and has just returned from a week abroad on business. “DG,” as his employees call him, launched his family’s holding company in 2003. Today the assets include 56% of the National Investment Bank of Mongolia, which he started in 2006 after buying the license of an old Russian bank, and brokerage firm National Securities. The real estate portfolio boasts land in central Ulaanbaatar and his Dream Land Resort near the country’s ancient capital of Kharkhorin. Mining drives the Mongolian boom, and Dagvadorj is in the thick of it, with numerous licenses for coal, rare earths and other resource-rich properties.

He credits sumo for his investing success. “Maybe my wrestler’s intuition helped me to see the opportunity to develop Mongolia,” he says through a translator (though he can get by on his English). He’s enjoyed years of red-hot growth, including a 17.3% jump in his country’s gross domestic product last year. Even as China’s demand for coal and other Mongolian exports slowed this year, the economy grew at a still sizzling 13.2% in the first half. So his strategy of not diversifying outside the country looks good, for now. “No investments outside of Mongolia,” he says. “Mongolia all the way.”

Aside from his wrestling savvy, Dagvadorj boasts another advantage?a U.S. investor, James Passin of the New York-based Firebird Fund. They met for dinner in Japan after a sumo match in 2005, and the next year Passin made his first trip to Mongolia before making his first investment there later in 2006 and launching his Mongolia-dedicated private equity fund in 2010. Some of the investments are made alongside Dagvadorj, and Firebird is the largest foreign owner of shares on the Mongolian Stock Exchange. Passin’s impression of DG hasn’t changed since that first dinner: “He’s a visionary. He saw what would happen in the Mongolian economy very early.” The two became fast friends. Dagvadorj and a brother surprised Passin last November by flying to New York to attend Passin’s 40th birthday party. That was “really special; my guests still talk about it,” says Passin.

Mongolia’s population is only 3 million, and with GDP expected to grow sixfold in this decade, the country may be among the top five in millionaires per capita by 2020, says Harris Kupperman of Mongolia Growth Group, an investment vehicle. Dagvadorj’s wealth will grow along with the country’s, but it’s difficult to say how rich he is already. None of his companies is listed?except for a small copper-and-gold play in which he holds a small stake?and valuing assets such as real estate and undeveloped mining properties in Mongolia is more than tricky. But estimates put his net worth at between $50 million and $75 million.

Dagvadorj was 11 when communism ended in 1991 and the Soviets exited Mongolia after 67 years. His parents and three siblings shared a tiny apartment, just 645 square feet, in Ulaanbaatar. During his teen years he witnessed some of the worst poverty in the country’s history. Lines for bread in the 1990s were longer than under communism because it would take more than a decade for capitalism to take off. Amid the pushing and shoving in lines, the future sumo champion earned a reputation for ensuring that the elderly got their bread.

In his teens Dagvadorj won a scholarship to study in Japan after scouts saw how good he was at Mongolian wrestling. His father, who worked as a driver, and his two brothers were also wrestlers. One brother, Sumiyabazar, now chairman of the family’s National Investment Bank, won the 2006 Naadam championship of Mongolian wrestling out of 1,024 contestants.

So Dagvadorj began sumo wrestling in 1999, at the age of 18. Eight months later he won his first tournament and was recruited into the Takasago stable of sumo and named “Morning Blue Dragon,” or Asash?ry?. (His full Japanese name is Asashuryu  Akinori.) He was the first to win all six major sumo tournaments in one calendar year. By the time he retired in early 2010 he had won 25 top division championships.

Dagvadorj’s career had not been without hiccups. In January 2010, after he won for the 25th time, reports surfaced that he had been drunk one night during the tournament and had punched a restaurant employee. The case was settled out of court and he alludes to the case being “quite different” from what the media reported. But he decided to retire at that point.

Back home in Mongolia rumors persist of Dagvadorj partying, getting into fights and having marital problems. As during his sumo career, he addresses accusations by letting his actions speak for him.

His employees do acknowledge that he can suddenly become angry but that he also calms down just as quickly. This trait must have served him well in sumo, they say, and serves him well in business now. They describe him as generous and kind, and they want people to know about his passion for developing Mongolia. They see him as a regular guy who’s an avid fisherman and golfer, albeit a regular guy who drives a Mercedes in the city, a Toyota Land Cruiser in the country (only 5% of the roads are paved and wintertime temperatures can dip to-40 ) and a Maybach for fun.

Dagvadorj’s investor friend Passin addresses the paradox of a bad boy and a good man: “He’s a very humble and loyal person, but he’s also a ferocious, very driven, very intense person. The forcefulness of his personality, and the generosity and humility of his personality, are expressed in different ways, which makes for a very dynamic person.”

For someone still so young, Dagvadorj is very active in philanthropy. In one project he’s building a hospital on property he owns by the Ulaanbaatar a irport to improve the country’s standard of health care. His Asashuryu Foundation has supported the Mongolian Olympic team, granted scholarships for Mongolian college students to study in Mongolia and Japan, and donated English language books to schools and community centers to support the effort to make English the country’s second language. The foundation also sponsors exceptional individual Mongolians, such as the then 15-year-old E. Enkhpurev, who was dubbed “Electron Boy” and participated in the Young Inventors Contest in Tokyo.

Dagvadorj has a son and a daughter. When asked if he wants his son to be a wrestler or if he aspires to have his children follow him into business, he replies, “I think I should raise them as good human beings, good people.”

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