On the eve of the 2018 marathon the mayor believes the tragedy has united the city. After winning the New York Marathon in November - becoming the first American woman to take the title since 1977 - Marblehead, Mass., native Flanagan is a favorite in Boston.
On the men's side, American Galen Rupp - who won the Chicago Marathon in October - looks to emerge victorious after a second-place finish in the 2017 Boston Marathon.
Later that year, the former University of OR star followed with a third-place finish at the Chicago Marathon, with an improved time of 2:20:57. Rupp took a bronze medal at the 2016 Rio Olympics then followed his Boston debut runner-up effort with a Chicago victory.
The cloud on Hasey's horizon, however, is that she has reportedly been suffering from a foot injury.
Last year, Hasay set the record for the fastest debut ever for an American woman in the Boston Marathon by three minutes, finishing third with a time of 2:23:00.
The run will be noticeably different for him this year.
Desiree Linden wins Boston Marathon after waiting for friend
Shalane Flanagan becomes the first USA woman since 1977 to win NYC Marathon.
A year ago the double world champion and victor of London and New York City titles followed up her Boston win by taking silver at the World Championships in London.
Men's victor Geoffrey Kirui running the 2017 Boston Marathon in Nike.
More recently Rupp has become only the second U.S. runner to break the hour mark for the half-marathon. She was also second to Rose Chelimo in the World Track and Field Championships marathon and fourth in NY.
Security at the marathon was heightened after the bombings, police say they are ready for Monday's race.