1921 U.S. National Championships – Men's singles
# 1921 U.S. National Championships – Men's singles

Defending champion Bill Tilden defeated Wallace Johnson in the final, 6–1, 6–3, 6–1 to win the men's singles tennis title at the 1921 U.S. National Championships. It was Tilden's second U.S. Championships singles title and fourth major singles title overall. Tilden became the first male tennis player to win four consecutive major singles events.

The tournament began on September 9, weeks after the conclusion of the corresponding Women's singles event, and ended on 19th. For the first time, the men's tournament was held at the Germantown Cricket Club in Philadelphia instead of at Forest Hills.

## Draw

### Key

* Q = Qualifier
* WC = Wild card
* LL = Lucky loser
* Alt = Alternate
* SE = Special exempt
* PR = Protected ranking
* ITF = ITF entry
* JE = Junior exempt
* w/o = Walkover
* r = Retired
* d = Defaulted
* SR = Special ranking

### Final eight

| Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Semifinals | Semifinals | Semifinals | Semifinals | Semifinals | Semifinals | Finals | Finals | Finals | Finals | Finals |
| - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - |
| Craig Biddle | Craig Biddle | 0 | 3 | 4 | | | | | | | | | | | | | |
| Wallace Johnson | Wallace Johnson | 6 | 6 | 6 | | | | | | | | | | | | | |
| Wallace Johnson | Wallace Johnson | 6 | 6 | 6 | | | Wallace Johnson | Wallace Johnson | 6 | 3 | 8 | 6 | | | | | |
| | | | | | | | James Anderson | James Anderson | 4 | 6 | 6 | 3 | | | | | |
| Frank Hunter | Frank Hunter | 1 | 3 | 4 | | | James Anderson | James Anderson | 4 | 6 | 6 | 3 | | | | | |
| James Anderson | James Anderson | 6 | 6 | 6 | | | | | | | | | | | | | |
| James Anderson | James Anderson | 6 | 6 | 6 | | | | | | | | | Wallace Johnson | Wallace Johnson | 1 | 3 | 1 |
| | | | | | | | | | | | | | Bill Tilden | Bill Tilden | 6 | 6 | 6 |
| Gordon Lowe | Gordon Lowe | 4 | 3 | 4 | | | | | | | | | | | | | | Bill Tilden | Bill Tilden | 6 | 6 | 6 |
| Bill Tilden | Bill Tilden | 6 | 6 | 6 | | | | | | | | | | | | | |
| Bill Tilden | Bill Tilden | 6 | 6 | 6 | | | Bill Tilden | Bill Tilden | 10 | 6 | 6 | | | | | | |
| | | | | | | | Willis Davis | Willis Davis | 8 | 2 | 1 | | | | | | |
| Willis Davis | Willis Davis | 6 | 4 | 6 | 1 | 6 | Willis Davis | Willis Davis | 8 | 2 | 1 | | | | | | |
| Robert Kinsey | Robert Kinsey | 3 | 6 | 4 | 6 | 4 | | | | | | | | | | | |

### Earlier rounds

**Section 1**

| Second round | Second round | Second round | Second round | Second round | Third round | Third round | Third round | Third round | Third round | Third round | Fourth round | Fourth round | Fourth round | Fourth round | Fourth round | Fourth round |
| - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - |
| Parker | Parker | 6 | 6 | 6 | | | | | | | | | | | | |
| Robinson | Robinson | 4 | 4 | 2 | | | | | | | | | | | | |
| | | | | | Parker | Parker | 6 | 4 | 1 | 3 | | | | | | |
| | | | | | Biddle | Biddle | 4 | 6 | 6 | 6 | | | | | | |
| Biddle | Biddle | 6 | 6 | 6 | | | | | | | | | | | | |
| Gilmore | Gilmore | 2 | 1 | 1 | | | | | | | | | | | | |
| | | | | | | | | | | | Biddle | Biddle | 6 | 3 | 6 | 6 |
| | | | | | | | | | | | Hammett | Hammett | 1 | 6 | 4 | 1 |
| Crawford | Crawford | 10 | 6 | 6 | | | | | | | | | | | | |
| Pannock | Pannock | 8 | 3 | 4 | | | | | | | | | | | | |
| | | | | | Crawford | Crawford | 3 | 6 | 2 | 4 | | | | | | |
| | | | | | Hammett | Hammett | 6 | 3 | 6 | 6 | | | | | | |
| Hammett | Hammett | 6 | 6 | 6 | | | | | | | | | | | | |
| Golden | Golden | 4 | 2 | 2 | | | | | | | | | | | | |

**Section 2**

| First round | First round | First round | First round | First round | First round | First round | Second round | Second round | Second round | Second round | Second round | Second round | Second round | Third round | Third round | Third round | Third round | Third round | Fourth round | Fourth round | Fourth round | Fourth round | Fourth round | Fourth round |
| - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - |
| | | | | | | | Knight | Knight | 6 | 6 | 6 | | | | | | | | | | | | | |
| | | | | | | | Hathaway | Hathaway | 4 | 2 | 1 | | | | | | | | | | | | | |
| | | | | | | | | | | | | | | Knight | Knight | 2 | 3 | 8 | | | | | | |
| Kinsey | Kinsey | 6 | 6 | 6 | | | | | | | | | | Kinsey | Kinsey | 6 | 6 | 10 | | | | | | |
| Putnam | Putnam | 1 | 3 | 4 | | | Kinsey | Kinsey | 6 | 6 | 6 | | | | | | | | | | | | | |
| Oelsner | Oelsner | 4 | 6 | 9 | 6 | | Oelsner | Oelsner | 2 | 4 | 4 | | | | | | | | | | | | | |
| Stockton | Stockton | 6 | 4 | 7 | 0 | | | | | | | | | | | | | | Kinsey | Kinsey | 6 | 6 | 2 | 1 |
| Edwards | Edwards | 6 | 7 | 5 | 6 | 6 | | | | | | | | | | | | | Johnson | Johnson | 4 | 8 | 6 | 6 |
| Vanneman | Vanneman | 3 | 9 | 7 | 3 | 1 | Edwards | Edwards | 4 | 6 | 6 | 4 | 6 | | | | | | | | | | | |
| Myers | Myers | 2 | 6 | 6 | 3 | 8 | Myers | Myers | 6 | 4 | 4 | 6 | 4 | | | | | | | | | | | |
| Gibbons | Gibbons | 6 | 0 | 1 | 6 | $7^r$ | | | | | | | | Edwards | Edwards | 0 | 1 | 2 | | | | | | |
| Washburn | Washburn | 6 | 6 | 6 | | | | | | | | | | Johnson | Johnson | 6 | 6 | 6 | | | | | | |
| Thayer | Thayer | 0 | 2 | 2 | | | Washburn | Washburn | 3 | 7 | 6 | 3 | 3 | | | | | | | | | | | |
| Johnson | Johnson | 6 | 6 | 6 | | | Johnson | Johnson | 6 | 5 | 2 | 6 | 6 | | | | | | | | | | | |
| Mercur | Mercur | 1 | 3 | 4 | | | | | | | | | | | | | | | | | | | | |

**Section 3**

| First round | First round | First round | First round | First round | First round | First round | Second round | Second round | Second round | Second round | Second round | Third round | Third round | Third round | Third round | Third round | Third round | Third round | Fourth round | Fourth round | Fourth round | Fourth round | Fourth round |
| - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - |
| Dionne | Dionne | 7 | 7 | 10 | | | | | | | | | | | | | | | | | | | |
| Evans | Evans | 5 | 5 | 8 | | | Dionne | Dionne | 3 | 1 | 1 | | | | | | | | | | | | |
| Fischer | Fischer | w. | o. | | | | Fischer | Fischer | 6 | 6 | 6 | | | | | | | | | | | | |
| Kashio | Kashio | | | | | | | | | | | Fischer | Fischer | 6 | 6 | 4 | 3 | 0 | | | | | |
| Hunter | Hunter | 6 | 5 | 6 | 3 | 6 | | | | | | Hunter | Hunter | 4 | 1 | 6 | 6 | 6 | | | | | |
| Anderson | Anderson | 3 | 7 | 3 | 6 | 3 | Hunter | Hunter | 6 | 6 | 6 | | | | | | | | | | | | |
| Bernstein | Bernstein | w. | o. | | | | Bernstein | Bernstein | 2 | 3 | 3 | | | | | | | | | | | | |
| Larned | Larned | | | | | | | | | | | | | | | | | | Hunter | Hunter | 6 | 6 | 6 |
| Baggs | Baggs | w. | o. | | | | | | | | | | | | | | | | Anderson | Anderson | 3 | 3 | 1 |
| Garland | Garland | | | | | | Baggs | Baggs | 1 | 2 | 0 | | | | | | | | | | | | |
| King | King | 6 | 6 | 6 | | | King | King | 6 | 6 | 6 | | | | | | | | | | | | |
| Ewing | Ewing | 3 | 1 | 4 | | | | | | | | King | King | 2 | 3 | 10 | | | | | | | |
| Jones | Jones | 6 | 6 | 6 | | | | | | | | Anderson | Anderson | 6 | 6 | 12 | | | | | | | |
| Sweet | Sweet | 0 | 1 | 1 | | | Jones | Jones | 2 | 2 | 1 | | | | | | | | | | | | |
| Anderson | Anderson | 6 | 6 | 6 | | | Anderson | Anderson | 6 | 6 | 6 | | | | | | | | | | | | |
| Baggs | Baggs | 2 | 2 | 1 | | | | | | | | | | | | | | | | | | | |

**Section 6**

| First round | First round | First round | First round | First round | First round | First round | Second round | Second round | Second round | Second round | Second round | Third round | Third round | Third round | Third round | Third round | Third round | Third round | Fourth round | Fourth round | Fourth round | Fourth round | Fourth round | Fourth round |
| - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - |
| Johnston | Johnston | 6 | 6 | 6 | | | | | | | | | | | | | | | | | | | | |
| Kelleher | Kelleher | 4 | 4 | 4 | | | Johnston | Johnston | 6 | 6 | 6 | | | | | | | | | | | | | |
| Hall | Hall | 2 | 3 | 7 | 8 | 7 | Hall | Hall | 4 | 1 | 4 | | | | | | | | | | | | | |
| Ackerland | Ackerland | 6 | 6 | 5 | 6 | 5 | | | | | | Johnston | Johnston | 2 | 3 | 6 | 9 | 6 | | | | | | |
| Hayes | Hayes | 6 | 6 | 6 | | | | | | | | Richards | Richards | 6 | 6 | 3 | 7 | 2 | | | | | | |
| Richards | Richards | 1 | 1 | 0 | | | Hayes | Hayes | 3 | 4 | 4 | | | | | | | | | | | | | |
| Richards | Richards | 6 | 6 | 3 | 6 | | Richards | Richards | 6 | 6 | 6 | | | | | | | | | | | | | |
| Herndon | Herndon | 1 | 1 | 6 | 4 | | | | | | | | | | | | | | Johnston | Johnston | 6 | 5 | 4 | 3 |
| Allen | Allen | 6 | 7 | 6 | | | | | | | | | | | | | | | Tilden | Tilden | 4 | 7 | 6 | 6 |
| Hennessey | Hennessey | 2 | 5 | 1 | | | Allen | Allen | 3 | 0 | 10 | | | | | | | | | | | | | |
| Shimizu | Shimizu | 6 | 6 | 6 | | | Shimizu | Shimizu | 6 | 6 | 12 | | | | | | | | | | | | | |
| Nielsen | Nielsen | 1 | 1 | 1 | | | | | | | | Shimizu | Shimizu | 4 | 4 | 1 | | | | | | | | |
| 7 | Tilden | | | | | | | | | | | Tilden | Tilden | 6 | 6 | 6 | | | | | | | | |
| 10 | Wright | | | | | | Tilden | Tilden | 6 | 6 | 6 | | | | | | | | | | | | | |
| | | | | | | | Goldsborough | Goldsborough | 2 | 1 | 4 | | | | | | | | | | | | | |

**Section 8**

| Second round | Second round | Second round | Second round | Second round | Third round | Third round | Third round | Third round | Third round | Third round | Third round | Fourth round | Fourth round | Fourth round | Fourth round | Fourth round |
| - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - |
| Rogers | Rogers | 6 | 6 | 6 | | | | | | | | | | | | |
| Martin | Martin | 1 | 4 | 2 | | | | | | | | | | | | |
| | | | | | Rogers | Rogers | 4 | 6 | 2 | 12 | 2 | | | | | |
| | | | | | Gallon | Gallon | 6 | 2 | 6 | 10 | 6 | | | | | |
| Gallon | Gallon | 6 | 6 | 6 | | | | | | | | | | | | |
| Neeley | Neeley | 3 | 1 | 2 | | | | | | | | | | | | |
| | | | | | | | | | | | | Gallon | Gallon | 0 | 1 | 4 |
| | | | | | | | | | | | | Kinsey | Kinsey | 6 | 6 | 6 |
| Kinsey | Kinsey | 6 | 6 | 6 | | | | | | | | | | | | |
| Watson | Watson | 3 | 2 | 2 | | | | | | | | | | | | |
| | | | | | Kinsey | Kinsey | 6 | 6 | 6 | | | | | | | |
| | | | | | Fall | Fall | 0 | 0 | 3 | | | | | | | |
| Fall | Fall | 7 | 6 | 6 | | | | | | | | | | | | |
| Wilson | Wilson | 5 | 1 | 2 | | | | | | | | | | | | |
