Acosta has been diagnosed with a mild left ankle sprain, while Hedges has a mild right knee sprain. No reason was given for Manneh's departure; he will join the Whitecaps on their preseason tour in Wales. The Gambia-born Manneh recently obtained his full US citizenship and is awaiting final FIFA clearance to be eligible for match play for the USMNT.
Monday's news leaves USMNT coach Bruce Arena with a 28-player roster ahead of upcoming friendlies against Serbia (in San Diego on Sunday; 4 pm ET, ESPN2, UniMas) and Jamaica (Feb. 3 in Chattanooga, Tennessee; 7 pm ET, FS1, UniMas, UDN).
Updated USMNT roster as of Jan. 23:
GOALKEEPERS (4): David Bingham (San Jose Earthquakes), Nick Rimando (Real Salt Lake), Luis Robles (New York Red Bulls), Brian Rowe (LA Galaxy)
DEFENDERS (9): DaMarcus Beasley (Unattached), Steve Birnbaum (D.C. United), Brad Evans (Seattle Sounders FC), Greg Garza (Atlanta United FC), Taylor Kemp (D.C. United), Chad Marshall (Seattle Sounders FC), Keegan Rosenberry (Philadelphia Union), Walker Zimmerman (FC Dallas), Graham Zusi (Sporting Kansas City)
MIDFIELDERS (10): Alejandro Bedoya (Philadelphia Union), Michael Bradley (Toronto FC), Benny Feilhaber (Sporting Kansas City), Jermaine Jones (LA Galaxy), Sacha Kljestan (New York Red Bulls), Sebastian Lletget (LA Galaxy), Dax McCarty (Chicago Fire), Darlington Nagbe (Portland Timbers), Chris Pontius (Philadelphia Union), Wil Trapp (Columbus Crew SC)
FORWARDS (5): Juan Agudelo (New England Revolution), Jozy Altidore (Toronto FC), Jordan Morris (Seattle Sounders FC), Chris Wondolowski (San Jose Earthquakes), Gyasi Zardes (LA Galaxy)