Current
| # | POS | Player | Club | Age | NATL | Previous Club |
|---|---|---|---|---|---|---|
| 23 | F | Eduardo | San Jose Earthquakes | 30 | Brazil | FC Basel (SWI) |
| 39 | F | Juan Agudelo | New York Red Bulls | 17 | Colombia | Red Bulls Academy |
| 3 | D | Korede Aiyegbusi | Kansas City Wizards | 22 | England | |
| 19 | F | Andre Akpan | Colorado Rapids | 22 | USA | |
| 3 | D | Chris Albright | New York Red Bulls | 31 | USA | New England Revolution (MLS) |
| 24 | M | Eric Alexander | FC Dallas | 22 | USA | Indiana University |
| 12 | M | Jean Alexandre | Real Salt Lake | 24 | Haiti | |
| 9 | F | Danny Allsopp | D.C. United | 32 | Australia | |
| 6 | M | Osvaldo Alonso | Seattle Sounders FC | 24 | Cuba | Charleston Battery (USL) |
| 30 | D | Kevin Alston | New England Revolution | 22 | USA | Indiana University |
| 10 | M/F | Arturo Alvarez | San Jose Earthquakes | 25 | USA | |
| 12 | F | Quincy Amarikwa | Colorado Rapids | 22 | USA | San Jose Earthquakes (MLS) |
| 9 | F | Juan Pablo Angel | New York Red Bulls | 34 | Colombia | Aston Villa (EPL) |
| 27 | M | Sammy Appiah | Houston Dynamo | 25 | Ghana | Boston University |
| 28 | M | Davy Armstrong | Colorado Rapids | 18 | USA | Rapids Academy |
| 22 | M | Davy Arnaud | Kansas City Wizards | 30 | USA | |
| 26 | D | Cristian Arrieta | Philadelphia Union | 30 | USA | Puerto Rico Islanders |
| 26 | M | Corey Ashe | Houston Dynamo | 24 | USA | |
| 3 | D | Nana Attakora | Toronto FC | 21 | Canada | |
| 8 | M | Stephane Auvray | Kansas City Wizards | 29 | Guadeloupe | Nimes Olympique (FRA) |
| 12 | M | Eric Avila | FC Dallas | 22 | USA | UC Santa Barbara |
| 8 | M | Mehdi Ballouchy | Colorado Rapids | 27 | Morocco | |
| 18 | D/M | Mike Banner | Chicago Fire | 25 | USA | SIU-Edwardsville |
| 24 | M/F | Brandon Barklage | D.C. United | 23 | USA | |
| 25 | D | Darrius Barnes | New England Revolution | 23 | USA | Duke University |
| 19 | F | Chad Barrett | Toronto FC | 25 | USA | Chicago Fire |
| 7 | M/F | Guillermo Barros Schelotto | Columbus Crew | 37 | Argentina | Boca Juniors (ARG) |
| 21 | D | Julien Baudet | Colorado Rapids | 31 | France | Crewe Alexandra (ENG) |
| 24 | F | Jamar Beasley | Kansas City Wizards | 30 | USA | Chicago Fire (MLS) |
| 5 | M | Kyle Beckerman | Real Salt Lake | 28 | USA |
Alumni
| # | POS | Player | Club | Age | NATL | Previous Club |
|---|---|---|---|---|---|---|
| 27 | D | Ubusuku Abukusumo | 33 | USA | ||
| 30 | F | Jose Abundis | 37 | Mexico | ||
| 28 | F | Adam Acosta | 28 | USA | ||
| 29 | D | Kevin Adams | 30 | Trinidad | ||
| 20 | D | Lyle Adams | 23 | Jamaica | Austin Aztex (USA) | |
| 33 | F | Nicholas Addlery | 28 | Jamaica | ||
| 14 | D | Joseph Addo | 38 | Ghana | ||
| 11 | M | Freddy Adu | 21 | Ghana | ||
| 34 | D | Vardan Adzemian | 26 | Armenia | ||
| 15 | F | Manuel Agogo | 31 | Ghana | ||
| 12 | D | Jeff Agoos | 42 | Switzerland | ||
| 4 | M | Roland Aguilera | 31 | Bolivia | ||
| 14 | F | Ade Akinbiyi | 35 | England | ||
| 2 | D | Nelson Akwari | 28 | USA | ||
| 35 | G | Charles Alamo | 25 | USA | ||
| 6 | M | Lazo Alavanja | 33 | USA | ||
| 3 | M | Johnny Alcaraz | 25 | USA | ||
| 4 | D | Jeremy Aldrich | 33 | USA | ||
| 13 | M | Jose Alegria | 29 | Peru | ||
| 20 | M/F | Ely Allen | 24 | USA | ||
| 22 | F | Yari Allnutt | 40 | USA | ||
| 24 | G | David Allred | ||||
| 4 | D | Chris Aloisi | 29 | USA | ||
| 17 | F | Josmer Altidore | 20 | USA | ||
| 28 | M | Cesar Alvarado | 31 | Mexico | ||
| 9 | M/F | Byron Alvarez | 31 | Mexico | ||
| 11 | F | Damian Alvarez | 37 | Mexico | ||
| 14 | M | Leonel Alvarez | 45 | Colombia | ||
| 17 | M | Pedro Alvarez | 40 | Colombia | ||
| 10 | F | Ricardo Alves Pereira | 22 | Brazil |
