The 33-year-old Bocanegra, captain since 2007, has lost his starting job with Racing Santander in Spain's second division. He was in the U.S. squad for the 2-1 loss at Honduras last month in the final round of qualifying but didn't play.
The United States heads into World Cup qualifiers against Costa Rica and Mexico with an inexperienced defense after dropping captain Carlos Bocanegra and learning eight players are injured or ill.
If Omar Gonzalez has absorbed one lesson over the past year, it's that the fast track to stardom isn't without its hurdles.
Jurgen Klinsmann is mixing it up for his first game as U.S. coach, taking a look at some up-and-coming players for the Aug. 10 exhibition against Mexico in Philadelphia.