Top-three women all break previous course record; Shalane Flanagan finishes seventh in 2:22:02, a personal best.
The 33-year-old Kenyan also won last year's Chicago Marathon.
There are eight men with sub-2:06 credentials, 12 women with sub-2:24 marks.
Lelisa Desisa and Rita Jeptoo won the men's and women's titles at this year's race.
The Kenyan smashes the course record and runs the fourth fastest marathon in history on Sunday.
The Kenyan is now in first place for the 2012-2013 series.
Running will endure and we will, too, because of running.
Rita Jeptoo first won Boston in 2006. Today, seven years later, the Kenyan repeated the feat.
All eyes are on Vincent Kipruto.