The latest Boston Marathon champion routinely runs 10 marathons per year, holds the world record for racing in a business suit and began 2018 by running in a race by himself in Massachusetts. 

On Monday, Yuki Kawauchi added to that eclectic resume, winning his first World Marathon Major, navigating awful weather and a field of men who were supposed to beat him handily to take victory in 2:15:58. 

Kawauchi made several bold moves throughout the race, the first of which came at the outset when he dropped a 4:37 mile into the wind. After he was reeled in by the 5K mark it seemed as if the race would revert to pre-race form. Geoffrey Kirui, the defending champion, Galen Rupp and a slew of Ethiopians and Kenyans comprised the main pack that ran together through the driving rain. With the exception of a few surges, most of which were initiated by Kawauchi, the pack ran conservatively through the middle portion of the race. 

At mile 17, Kirui made a move that scattered the group and looked to put the race to bed. The Kenyan effortlessly increased his lead to 70 seconds at the 20-mile mark as Rupp and the other challengers weren't able to respond. At the 35K mark, Kawauchi solidified his position in second place, but he was now 91 seconds behind Kirui. 

That's where things began to change. 

Kirui's next four miles were 5:24, 5:04, 5:19 and 5:31. The latter splits opened a door for Kawauchi as Kirui looked as if the weather was finally taking its toll. By 40K, the lead had now shrunk to 20 seconds, with Kirui clearly struggling. Kawauchi's eventual pass was decisive. 

As expected, Kirui wasn't able to counter as his earlier sub five miles had now been reduced to a shuffle.

Kawauchi didn't look back and crossed the line in 2:15:58, unable to hide the shock on his face. With the win, he became the first Japanese man to top the podium in Boston since 1987. 

Kirui finished 2:25 behind in 2:18:23 and Americans Shadrack Biwott and Tyler Pennel took third and fourth in 2:18:35 and 2:18:57, respectively. Galen Rupp did not finish the race. His last split was recorded at the 30K mark. 

Check out mile-by-mile analysis of the race.