Yuki Kawauchi outdueled London Olympian Kentaro Nakamoto to win Sunday's Beppu-Oita Marathon in a race-record time of 2 hours, 8 minutes, 15 seconds.

The pair burst away from the field after 28 km, and Kawauchi put Nakamoto in the rearview mirror after the 40-km mark. Nakamoto, who was sixth at last summer's Olympic marathon, finished 20 seconds back in second place.

"Today was really a great time," said Kawauchi, who balances his running career with his day job as a public officer with Saitama's prefectural government. "He was an Olympian in London, so I wouldn't have been ashamed to lose to him. I just kept pushing forward."

Kawauchi's time was a personal best, surpassing the 2:08:37 he ran when he finished third in the 2011 Tokyo Marathon. Nakamoto's time was also a personal best.

"I was hoping for a victory, so of course I feel disappointed," said Nakamoto. "I need to be able to turn on the speed in the last 2 km. I wanted to compete (with Kawauchi) at a high level. But because of him I was able to produce a good time. He has become a rival I don't want to lose to."

The Beppu-Oita race is one of the marathons used in determining the men who will represent Japan in the next world athletics championships.