Simms went undrafted by Major League Soccer after college and instead signed with Richmond Kickers of the A-League. Although he had a relatively impressive first season with the Kickers and started 28 games for the club, Simms's talent was not really recognized until he was called into the United States national team camp as a replacement player due to a conflict between the United States Soccer Federation and the players in 2005. Simms greatly impressed in camp and, when the disagreement was settled, Simms was asked to remain in camp and train with the regular team.