In the women’s race, Flanagan, a four-time Olympian and 2017 TCS New York City Marathon champion, will face Jordan Hasay, who finished third at the Chicago Marathon in October clocking 2:20:57. She set the US marathon debut record in Boston in April when she ran 2:23:00.
Also joining the women’s field are Molly Huddle, Desiree Linden and Deena Kastor.
Huddle, the national record holder at 10,000m with 30:13.17, made a strong marathon debut at the 2016 edition of the New York Marathon, finishing third.
Kastor, 44, the 2004 Olympic bronze medallist in the marathon, is the US record holder over the distance at 2:19:36, set when winning the 2006 London Marathon.
Linden, a two-time Olympian, returns after finishing fourth in Boston last year. She has a 2:22:38 lifetime best, also set in Boston, from 2011 when she finished second.
Rupp, the 2016 Olympic bronze medallist, returns to Boston after finishing runner-up in April and after a taking a commanding victory at October’s Chicago Marathon.
He’ll face Dathan Ritzenhein, the third fastest US marathoner of all time with a 2:07:47 personal best, and Abdi Abdirahman, who was sixth in Boston this year and seventh in New York.
Shadrack Biwott, who was fourth last year, will also return.
Organisers announced last week that 2017 winners Edna Kiplagat and Geoffrey Kirui will return to defend their titles.
Organisers for the IAAF