TOKYO (Reuters) - Yuki Kawauchi’s improbable victory at the Boston Marathon on Monday was the crowning glory in the career of an amateur Japanese runner who has defied every convention in modern athletics.

Apr 16, 2018; Boston, MA, USA; Yuki Kawauchi leads the pack during the 2018 Boston Marathon near mile marker 26. Mandatory Credit: Paul Rutherford-USA TODAY Sports

The 31-year-old from Saitama, the first Japanese man to win the Boston Marathon since Toshihiko Seko in 1987, holds down a full-time job at a local school and trains without the aid of a coach or sponsorship.

He has competed in more than 80 marathons.

After splashing across the finish line through wind and rain ahead of defending champion Geoffrey Kirui of Kenya on Monday, Kawauchi knew he had surprised a few people.

“I don’t think there was a single person in Boston who thought I would win this today,” he said with a smile.

Many of Kawauchi’s marathon wins have come in poor weather.

“I think the conditions were instrumental in being able to win,” he said. “In the marathon you never know what could happen. I think the conditions were instrumental in being able to win.”

Kawauchi has won his last five marathons, including four in 2018, and ran 12 last year. Kenya’s Olympic champion Eluid Kipchoge ran only two in 2017.

“I love to run races,” Kawauchi said. “Races gives me the opportunity to travel and in a more practical sense, because I train by myself if I didn’t put in a lot of races I wouldn’t be able to put in the same quality.”

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MAJOR EVENTS

Kawauchi has not fared well at major events, however, finishing 18th at the 2011 and 2013 World Championships and ninth in London last year. He has never been selected for the Japanese Olympic team.

Kawauchi’s personal best of 2:08:14, recorded in 2013, would have been enough to win gold at a rainy Rio Games but it is more than five minutes outside the world record. He has only once run under 2:10:00 since July, 2016.

Kawauchi, who holds the record for the most sub-2.20 marathons, said last year that being able to fit in only one training session a day had helped him.

“When you consider that runners belonging to teams are doing 12km a day on average in their morning runs, my monthly mileage is going to be at least 360km less since I don’t do them,” he said.

“I’m pretty sure the human body has a mileage limit.”

Kawauchi was born in 1987, the same year Seko won the Boston Marathon, and Seko hopes Monday’s victory proves to be a turning-point for Japanese marathon running.

“I want Kawauchi’s resolve to be followed by other athletes,” Seko said in a statement released by the JAAF, where he now leads the organisation’s high-performance marathon team.

“(Yuta) Shirata broke the Japanese record and Kawauchi won the Boston marathon for the first time in 31 years.”

“Now it is a new era of (Japanese) marathon running.”

Japan last won Olympic marathon gold through Mizuki Nogushi in Athens in 2004 and the country’s women have won two golds among four medals at the Games.

However, the only Japanese man to win Olympic gold was Sohn Kee-chung in 1936, a Korean athlete competing for Japan because his country was under the rule of the Japanese at the time.

The last time a Japanese man won an Olympic marathon medal was in Barcelona in 1992.