After slow start, with the leaders covering the first kilometre in 3:11 and the second kilometre in 3:10, the pace picked up and 5km was reached in 15:27.
The pace then steadily increased: 5km to 10km took 15:08, and the 10-15km split was 14:53.
By 20km, passed in 1:00:43, the lead pack contained 10 runners. At 30km, with a split of 1:31:54), shortly after the pace makers left the course, there were still six runners in contention at the front: Estifanos, Uganda’s 2014 champion Abraham Kiplimo and the Japanese quartet of Kadota, Yamamoto, Yusei Nakao and Satoshi Yoshii.
However, Estifanos soon started to increase the pace and Nakao and Yoshii were left behind.
The defending champion Kiplimo was the next to let go, leaving Estifanos, Kadota and Yamamoto to fight it out for the top spot on the podium.
Estiganos surged again after 32km; first Yamamoto and then, finally, Kadota had to let him go.
At 35km, the Eritrean was 10 seconds ahead of Kadota who, in turn, was another 10 seconds ahead of Yamamoto.
After 35km, Estifanos steadily slowed, taking 15:52 between 35km and 40km, but he still increased his advantage over his flagging pursuers and won by 28 seconds.
Estifanos became the first Eritrean to win the Beppu-Oita Marathon in its 64 years history and it continued his upward curve over the classic distance. It was the fourth straight personal best in as many marathons and his finishing position has also improved in those four races.
He made his marathon debut in the 2013 Beppu-Oita Marathon, where he was 11th with 2:16:13. Next was the 2013 Gold Coast Marathon where Estifanos improved his time to 2:13:10, when he finished third, and in the 2014 Melbourne Marathon Estifanos improved to second with 2:11:47.
Kadota finished second with 2:10:46, nearly two minutes better than his previous best of 2:12:25, which was recorded in the 2012 Beppu-Oita Marathon.
Yamamoto, a marathon debutant with a half marathon best of 1:02:43, was third with 2:11:48 while Kiplimo fell off the pace after 30km and finished fourth with 2:12:23.
Kiplimo was followed home by Satoshi Yoshii, Naoki Okamoto in 2:12:48 and 2:12:55 respectively.
Ken Nakamura for the IAAF