The USA has reached the Confederations Cup semifinals once before, falling to host Mexico in 1999.
Jonathan Bornstein, Michael Bradley, Oguchi Onyewu and Jonathan Spector are carrying yellow cards into the Spain match. Another caution would mean suspension for the final or third-place game.
U.S. captain Carlos Bocanegra, who missed the first three games game with a hamstring strain is questionable for Wednesday's game. Playing in place of Bocanegra has been Jay DeMerit, who played the full 90 in each of the first three games.
Jonathan Spector, whose cross set up the USA's third goal, by Clint Dempsey, in its 3-0 win over Egypt that ensured passage into semifinal, has played every minute at right back, the position usually manned by the injured Steve Cherundolo or Frankie Hejduk.
Dempsey's goal was the 14th of his career, moving him into sole possession of ninth place on the all-time scoring list for the U.S., passing Marcelo Balboa and Hugo Perez, and one behind Cobi Jones in eighth place.
Bradley, who scored the second goal against Egypt, now his six for the USA, matching former U.S. midfielder John Harkes.
Spain's roster of 23 players includes 22 who closed out their 2008-09 season with clubs that qualified for either UEFA Champions League or Europa League. By contrast, only Dempsey (Fulham), keeper Tim Howard (Everton), Oguchi Onyewu (Standard Liege) and DaMarcus Beasley (Rangers) were with clubs at the end of the season that qualified for European tournaments.
Click HERE for video of the three U.S. goals against Egypt that took the USA into the semifinals.