# 1920 Australasian Championships – Singles

Pat O'Hara Wood defeated Ronald Thomas 6–3, 4–6, 6–8, 6–1, 6–3 in the final to win the men's singles tennis title at the 1920 Australasian Championships.

## Draw
### Key

* Q = Qualifier
* WC = Wild card
* LL = Lucky loser
* r = Retired
| Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Semifinals | Semifinals | Semifinals | Semifinals | Semifinals | Semifinals | Semifinals | Finals | Finals | Finals | Finals | Finals | Finals | Finals |
| Pat O'Hara Wood | Pat O'Hara Wood | 6 | 6 | 6 | | | | | | | | | | | | | | | | |
| H. Utz | H. Utz | 1 | 1 | 2 | | | Pat O'Hara Wood | Pat O'Hara Wood | 6 | 6 | 7 | | | | | | | | | |
| A. Roy Taylor | A. Roy Taylor | 3 | 3 | 6 | 6 | 6 | A. Roy Taylor | A. Roy Taylor | 3 | 1 | 5 | | | | | | | | | |
| A. Scott | A. Scott | 6 | 6 | 2 | 2 | 3 | | | | | | | | Pat O'Hara Wood | Pat O'Hara Wood | 6 | 4 | 6 | 6 | 6 |
| Ronald Thomas | Ronald Thomas | 6 | 6 | 6 | | | | | | | | | | Ronald Thomas | Ronald Thomas | 3 | 6 | 8 | 1 | 3 |
| G. O'Dea | G. O'Dea | 0 | 2 | 4 | | | Ronald Thomas | Ronald Thomas | 6 | 4 | 6 | 5 | 6 | | | | | | | |
| Horace Rice | Horace Rice | 6 | 6 | 6 | | | Horace Rice | Horace Rice | 4 | 6 | 1 | 7 | 2 | | | | | | | |
| C. Gurner | C. Gurner | 2 | 2 | 2 | | | | | | | | | | | | | | | | |

### Top half

| First round | First round | First round | First round | First round | First round | Second round | Second round | Second round | Second round | Second round | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Semifinals | Semifinals | Semifinals | Semifinals |
| | | | | | | P. O'Hara Wood | 6 | 6 | 6 | | | | | | | | | | | |
| K. Roberts | 9 | 6 | 2 | 0 | 6 | K. Roberts | 0 | 2 | 2 | | | | | | | | | | | |
| R. Berriman | 7 | 1 | 6 | 6 | 2 | | | | | | P O'Hara Wood | 6 | 6 | 6 | | | | | | |
| H. Utz | 6 | 6 | 5 | 3 | 11 | | | | | | H. Utz | 1 | 1 | 2 | | | | | | |
| J. Penny | 4 | 4 | 7 | 6 | 9 | H. Utz | 6 | 6 | 6 | | | | | | | | | | | |
| | | | | | | R. Paxton | 2 | 1 | 1 | | | | | | | | | | | |
| | | | | | | | | | | | | | | | | | P O'Hara Wood | 6 | 6 | 7 |
| A. R. Taylor | 7 | 6 | 6 | 5 | 6 | | | | | | | | | | | | A. R. Taylor | 3 | 1 | 5 |
| E. Jordan | 9 | 3 | 3 | 7 | 3 | A. R. Taylor | 6 | 6 | 9 | 6 | | | | | | | | | | |
| E. Rowe | 6 | 8 | 6 | | | E. Rowe | 2 | 4 | 11 | 3 | | | | | | | | | | |
| G Hone | 3 | 6 | 2 | | | | | | | | A. R. Taylor | 6 | 6 | 2 | 2 | 6 | | | | |
| A. Scott | 8 | 6 | 6 | | | | | | | | A. Scott | 3 | 3 | 6 | 6 | 3 | | | | |
| E. Hicks | 6 | 2 | 4 | | | A. Scott | 6 | 4 | 6 | 6 | | | | | | | | | | |
| | | | | | | R. Billing | 4 | 6 | 3 | 4 | | | | | | | | | | |

### Bottom half

| First round | First round | First round | First round | Second round | Second round | Second round | Second round | Second round | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Semifinals | Semifinals | Semifinals | Semifinals | Semifinals | Semifinals |
| R. Thomas | w/o | | | | | | | | | | | | | | | | | |
| E. Richmond | | | | R. Thomas | 6 | 8 | 6 | | | | | | | | | | | |
| S. Milligan | 6 | 6 | 6 | S. Milligan | 2 | 6 | 0 | | | | | | | | | | | |
| F. Bromley | 2 | 2 | 1 | | | | | | R. Thomas | 6 | 6 | 6 | | | | | | |
| G. O'Dea | 6 | 6 | 6 | | | | | | G. O'Dea | 0 | 2 | 4 | | | | | | |
| T. Linn | 2 | 0 | 4 | G. O'Dea | 6 | 1 | 6 | 6 | | | | | | | | | | |
| | | | | F. Hone | 1 | 6 | 2 | 3 | | | | | | | | | | |
| | | | | | | | | | | | | | R. Thomas | 6 | 4 | 6 | 5 | 6 |
| H. Rice | 6 | 6 | 6 | | | | | | | | | | H. Rice | 4 | 6 | 1 | 7 | 2 |
| C. Stuart | 3 | 2 | 2 | H. Rice | 7 | 6 | 6 | | | | | | | | | | | |
| J. O'Dea | 6 | 6 | 9 | J. O'Dea | 5 | 1 | 1 | | | | | | | | | | | |
| A. Pittman | 0 | 2 | 7 | | | | | | H. Rice | 6 | 6 | 6 | | | | | | |
| | | | | | | | | | C. Gurner | 2 | 2 | 2 | | | | | | |
| | | | | C. Gurner | 6 | 7 | 7 | | | | | | | | | | | |
| | | | | F. Barritt | 1 | 5 | 5 | | | | | | | | | | | |