She set a world's best 12K time last weekend in Alexandria, Virginia.
Mary Cain announced last week that she was turning professional.
Huddle and Flanagan notched the two fastest 12K road running performances in history.
Shalane Flanagan, Molly Huddle and Emily Infeld will lead the way in the inaugural event.
There were some fast races on the day before the New York City Marathon!
Course-record finishes light up the Big Apple streets on the day before the New York City Marathon.
American runners had a good showing last week in Moscow!
She wanted to race the 1500m as well, but a clerical error cost her a spot in that event.
The 27-year-old has set three PRs since June, including in the 3000m in London over the weekend.
Men's, women's 800m winners triumph in quick fashion on the final day of the USA Outdoor Track & Field Championships.