The 2021 Lamar Hunt U.S. Open Cup tournament proper was to feature teams from all five tiers of the men's American soccer pyramid.
Qualification for the 2021 tournament was drastically altered due to the ongoing COVID-19 pandemic. The tournament itself was downsized to 16 teams, before ultimately being canceled for the second consecutive season due to the pandemic.
The top eight American-based teams based in the regular season standings after three weeks of the season, taken on a points-per-game (PPG) basis, were set to qualify for the tournament before its cancellation.[1] Qualification began on April 16, 2021, and concluded on May 2, 2021.
Source: MLS Rules for classification: 1) points per game; 2) goal differential per game; 3) goals scored per game; 4) disciplinary points per game; 5) away goal differential per away game; 6) away goals scored per away game; 7) home goal differential per home game; 8) home goals scored per home game; 9) coin toss or drawing of lots[2]
The four semifinalists from the USL Championship playoffs qualified. Qualification retroactively began on October 10, 2020, and ended on October 17, 2020.
Source: 2020 USL League One standings Rules for classification: 1) points; 2) total wins; 3) total goal differential; 4) total goals scored; 5) points earned against top four Conference finishers; 6) disciplinary points; 7) coin toss or drawing of lots Notes:
^ abcdProfessional teams that are owned by teams playing in a higher division are ineligible for the U.S. Open Cup.
Final
The game was canceled the day before because several Union Omaha players tested positive for COVID-19. Greenville was awarded the title based on points per game average (2.188 to 1.825), and reached the Open Cup.[3]