Sixteen teams were entered in this round, and were drawn into eight matchups that were contested in a two-legged tie.
This tournament's preliminary round was scheduled to begin one month earlier than the previous season in order to alleviate schedule congestion for participants due to fourth round of CONCACAF qualification for the 2010 FIFA World Cup.
[1] The matchup draw for the preliminary and group stages was conducted on June 11.
[2] The match schedule was announced five days later on June 16.
Puerto Rico Islanders won 1–0 on aggregate.