The 2010 Lamar Hunt U.S. Open Cup tournament proper features teams from the top five levels of the American Soccer Pyramid. These five levels, namely Major League Soccer, the United Soccer Leagues (First Division, Second Division, and Premier Development League), and the United States Adult Soccer Association, each have their own separate qualification process to trim their ranks down to their final team delegations in the months leading up to the start of the tournament proper.
The 2010 Cup will feature 8 teams from the MLS, 9 from the USSF Division 2 (being all 9 US-based teams), all 6 teams from the USL Second Division, 8 teams from the PDL, 8 from USASA, and an additional team resulting from a single match between Sonoma County Sol of the National Premier Soccer League and PSA Los Gatos Storm of US Club Soccer. The eight clubs from MLS will receive byes into the Third Round.
The top six MLS clubs in the 2009 standings were given six of the berths into the Third Round while the nine remaining U.S.-based clubs will compete for the final two berths via a playoff.
Note: Scorelines use the standard U.S. convention of placing the home team on the right-hand side of box scores.
New York Red Bulls qualify for the Round of 16.
D.C. United qualify for the Round of 16.