Felix, who also won the Olympic 200 meters, will be joined by her teammates on the Olympic 4x400 - Sanya Richards-Ross, DeeDee Trotter, and Francena McCorory. Two other members of the 4x100 unit, Tianna Madison Bartoletta and Bianca Knight, will be coming to Penn.
The U.S. men's silver- medal-winning 4x100 team will be represented by Trell Kimmons, Justin Gatlin, and Ryan Bailey. Tony McQuay and Manteo Mitchell, members of the silver-medal-winning 4x400 team, will be there along with LaShawn Merritt, who did not run in the Olympic relay because of an injury.
As always, Jamaica will be the chief challenger for the Americans in both 4x100 races. The Jamaican women finished second in London and will bring two-time gold medalist Shelly-Ann Fraser-Pryce, Sherone Simpson, and Kerron Stewart from that unit.
Nesta Carter, part of the Jamaican team that set a world record of 36.84 seconds in the men's 4x100 in London, will compete on Saturday.
USA vs. the World relays include the men's distance medley and the women's 4x800. The United States went 6 for 6 in last year's competition.
Heptathlon's first day
Penn State junior Brittney Howell, a graduate of Cheltenham High School, posted the best marks in three of the four events and took the first-day lead in the women's heptathlon, the initial event of the 2013 Penn Relay Carnival.
Howell tallied 3,197 points. Lindsey Hufnagel of Western Michigan was second with 2,923 points, and Alexis Easterling of Coppin State stood third with 2,874.
The heptathlon will conclude Wednesday.