Both are repeat winners of the road race.
Five past champions will be racing, and it will be televised nationally.
The race adjacent to Central Park featured fast times and photo finishes.
The American won the race down one of New York's most famous streets in 2011 and 2013.
The American is seeking her third victory at the annual dash in New York City.
The 18-year-old won the world junior 3000m title in July.
The 23-year-old took fourth at the Fifth Avenue Mile.
Here's a look at how the elite runners did in the annual dash down one of New York City's famous streets.
Nick Willis was well under 4 minutes for the men.