Zimmerman is a defender who starts for FC Dallas in MLS.
Goalkeeper Cody Cropper, a player who grow up in Norcross and Duluth, was also selected. He plays professionally for ML Dons in England.
The U.S. will play Colombia in Barranquilla at 4 p.m. Friday. The return leg will be played in Frisco Texas at 8:30 p.m. on March 29. The team that earns the most points will advance to the Olympics in Brazil.
The U.S. U-23 roster in full:
Goalkeepers: Cody Cropper (Milton Keynes Dons), Ethan Horvath (Molde), Zach Steffen (Freiburg)
Defenders: Kellyn Acosta (FC Dallas), Matt Miazga (Chelsea), Eric Miller (Colorado Rapids), Tim Parker (Vancouver Whitecaps), Desevio Payne (Groningen), Shane O’Neill (Cambridge United), Brandon Vincent (Chicago Fire), Walker Zimmerman (FC Dallas)
Midfielders: Fatai Alashe (San Jose Earthquakes), Paul Arriola (Club Tijuana), Luis Gil (Queretaro), Julian Green (Bayern Munich), Emerson Hyndman (Fulham), Jerome Kiesewetter (Stuttgart), Matt Polster (Chicago Fire), Dillon Serna (Colorado Rapids), Wil Trapp (Columbus Crew)
Forwards: Jordan Morris (Seattle Sounders), Mario Rodriguez (Borussia Monchengladbach), Khiry Shelton (New York City FC)
