CHICAGO — The United States Wednesday added Philadelphia Union defender Auston Trusty to the U.S. roster while releasing defender Marlon Fossey.

Fossey entered training camp carrying a groin injury but held hopes of healing enough to play in the tournament.

Trusty has been with the team as an alternate in case of injury since the team departed for training camp in Japan May 10.

The U-20 MNT roster remained at 21 players. The team arrived in Incheon, Korea Republic late Wednesday night ahead of its opening match against Ecuador at Incheon Stadium Saturday (4 a.m. ET; FS1). Fans can follow the USA’s games on U.S. Soccer’s official Facebook, Twitter (@ussoccer_ynt) and Instagram (@ussoccer_ynt).

The U.S. roster:

GOALKEEPERS (3): Jonathan Klinsmann (University of California; Newport Beach, Calif.), J.T. Marcinkowski (Georgetown; Alamo, Calif.), Brady Scott (De Anza Force; Petaluma, Calif.)

DEFENDERS (7): Danny Acosta (Real Salt Lake; Salt Lake City, Utah), Cameron Carter-Vickers (Tottenham Hotspur FC; Westcliff-on-Sea, England), Justen Glad (Real Salt Lake; Tucson, Ariz.), Aaron Herrera (University of New Mexico; Las Cruces, N.M.), Erik Palmer-Brown (Sporting Kansas City; Lee’s Summit, Mo.), Tommy Redding (Orlando City SC; Oviedo, Fla.), Auston Trusty (Philadelphia Union; Media, Pa.)

MIDFIELDERS (5): Tyler Adams (New York Red Bulls; Wappingers Falls, N.Y.), Luca De La Torre (Fulham FC; San Diego, Calif.), Derrick Jones (Philadelphia Union; Philadelphia, Pa.), Eryk Williamson (University of Maryland; Alexandria, Va.), Gedion Zelalem (Arsenal FC; Bethesda, Md.)

FORWARDS (6): Jeremy Ebobisse (Portland Timbers; Bethesda, Md.), Lagos Kunga (Atlanta United FC Academy; Tucker, Ga.) Brooks Lennon (Real Salt Lake; Paradise Valley, Ariz.), Emmanuel Sabbi (Unattached; Columbus, Ohio), Josh Sargent (St. Louis Scott Gallagher Missouri; O’Fallon, Mo.), Sebastian Saucedo (Real Salt Lake; Park City, Utah)