# 2021 Los Cabos Open – Singles

Diego Schwartzman was the reigning champion from when the tournament was last held in 2019, but chose to compete at the Summer Olympics instead.
Cameron Norrie won his maiden ATP Tour title, defeating Brandon Nakashima in the final, 6–2, 6–2.

## Seeds

The top 4 seeds receive a bye into the second round.
* Cameron Norrie (champion)
* John Isner (semifinals)
* Taylor Fritz (semifinals)
* Sam Querrey (second round)
* Jordan Thompson (quarterfinals)
* Steve Johnson (quarterfinals)
* Andreas Seppi (first round)
* Mackenzie McDonald (first round)

## 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

### Finals

| Semifinals | Semifinals | Semifinals | Semifinals | Final | Final | Final | Final |
| 1 | Cameron Norrie | 6 | 6 | | | | |
| 3 | Taylor Fritz | 3 | 1 | | | | |
| 3 | Taylor Fritz | 3 | 1 | 1 | Cameron Norrie | 6 | 6 |
| | | | | | Brandon Nakashima | 2 | 2 |
| | Brandon Nakashima | 7 | 6 | | Brandon Nakashima | 2 | 2 |
| 2 | John Isner | 5 | 4 | | | | |

### Top half

| First round | 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 |
| | | | | | 1 | C Norrie | 7$^7$ | 6 | | | | | | | | | |
| Q | M Ebden | 5 | 1 | | | E Ymer | 6$^4$ | 3 | | | | | | | | | |
| | E Ymer | 7 | 6 | | | | | | | 1 | C Norrie | 6 | 6 | | | | |
| WC | T Kokkinakis | 6 | 6$^4$ | 6$^3$ | | | | | | Q | E Escobedo | 1 | 1 | | | | |
| | D Kudla | 4 | 7$^7$ | 7$^7$ | | D Kudla | 4 | 6$^9$ | | | | | | | | | |
| Q | E Escobedo | 6 | 6 | | Q | E Escobedo | 6 | 7$^{11}$ | | | | | | | | | |
| 8 | M McDonald | 3 | 4 | | | | | | | | | | | 1 | C Norrie | 6 | 6 |
| | | | | | | | | | | | | | | 3 | T Fritz | 3 | 1 |
| | | | | | 3 | T Fritz | 6 | 6$^9$ | 7 | | | | | | | | |
| | P Gojowczyk | 3 | 2 | | | I Marchenko | 1 | 7$^{11}$ | 5 | | | | | | | | |
| | I Marchenko | 6 | 6 | | | | | | | 3 | T Fritz | 6 | 6 | | | | |
| Q | A Sarkissian | 7 | 0 | 4 | | | | | | 6 | S Johnson | 4 | 4 | | | | |
| | Y Uchiyama | 5 | 6 | 6 | | Y Uchiyama | 6$^4$ | 3 | | | | | | | | | |
| WC | G López Villaseñor | 6$^4$ | 2 | | 6 | S Johnson | 7$^7$ | 6 | | | | | | | | | |
| 6 | S Johnson | 7$^7$ | 6 | | | | | | | | | | | | | | |

### Bottom half

| 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 | Semifinals | Semifinals | Semifinals | Semifinals |
| 5 | J Thompson | 6 | 7 | | | | | | | | | | | | | | | |
| WC | I Karlović | 4 | 5 | | 5 | J Thompson | 3 | 6 | 7 | | | | | | | | | |
| | J Rodionov | 3 | 1$^r$ | | | S Ofner | 6 | 4 | 5 | | | | | | | | | |
| | S Ofner | 6 | 3 | | | | | | | 5 | J Thompson | 3 | 6 | 6$^4$ | | | | |
| | B Nakashima | 6 | 6$^5$ | 6 | | | | | | | B Nakashima | 6 | 4 | 7$^7$ | | | | |
| | J. J. Wolf | 3 | 7$^7$ | 2 | | B Nakashima | 6 | 6 | | | | | | | | | | |
| | | | | | 4 | S Querrey | 3 | 4 | | | | | | | | | | |
| | | | | | | | | | | | | | | | | B Nakashima | 7 | 6 |
| 7 | A Seppi | 6 | 2 | 3 | | | | | | | | | | | 2 | J Isner | 5 | 4 |
| | A Bolt | 0 | 6 | 6 | | A Bolt | 6 | 6 | | | | | | | | | | |
| | E Gómez | 6 | 6 | | | E Gómez | 3 | 1 | | | | | | | | | | |
| Q | N Mejía | 4 | 1 | | | | | | | | A Bolt | 3 | 4 | | | | | |
| | J Jung | 1 | 4 | | | | | | | 2 | J Isner | 6 | 6 | | | | | |
| | E Donskoy | 6 | 6 | | | E Donskoy | 5 | 6 | 6$^5$ | | | | | | | | | |
| | | | | | 2 | J Isner | 7 | 3 | 7$^7$ | | | | | | | | | |

## Qualifying
### Seeds

* Ernesto Escobedo (qualified)
* Ruben Bemelmans (qualifying competition)
* Matthew Ebden (qualified)
* Yosuke Watanuki (qualifying competition, retired)
* Nicolás Mejía (qualified)
* John-Patrick Smith (qualifying competition)
* Alex Rybakov (qualifying competition)
* Raymond Sarmiento (first round)

### Qualifiers

* Ernesto Escobedo
* Nicolás Mejía
* Matthew Ebden
* Alexander Sarkissian

### Qualifying draw
#### First qualifier

| First round | First round | First round | First round | Qualifying competition | Qualifying competition | Qualifying competition | Qualifying competition |
| 1 | Ernesto Escobedo | 7$^7$ | 6 | | | | |
| | Ricardo Rodríguez | 6$^4$ | 3 | | | | |
| | Ricardo Rodríguez | 6$^4$ | 3 | 1 | Ernesto Escobedo | 6 | 7$^7$ |
| | | | | 7 | Alex Rybakov | 2 | 6$^3$ |
| | Gage Brymer | 3 | 4 | 7 | Alex Rybakov | 2 | 6$^3$ |
| 7 | Alex Rybakov | 6 | 6 | | | | |

#### Second qualifier

| First round | First round | First round | First round | First round | Qualifying competition | Qualifying competition | Qualifying competition | Qualifying competition |
| 2 | Ruben Bemelmans | 7$^7$ | 7$^7$ | | | | | |
| WC | Lucas Gómez | 6$^3$ | 6$^5$ | | | | | |
| WC | Lucas Gómez | 6$^3$ | 6$^5$ | | 2 | Ruben Bemelmans | 3 | 6$^2$ |
| | | | | | 5 | Nicolás Mejía | 6 | 7$^7$ |
| | Alex Hernández | 3 | 6 | 5 | 5 | Nicolás Mejía | 6 | 7$^7$ |
| 5 | Nicolás Mejía | 6 | 3 | 7 | | | | |

#### Third qualifier

| First round | First round | First round | First round | Qualifying competition | Qualifying competition | Qualifying competition | Qualifying competition |
| 3 | Matthew Ebden | 6 | 6 | | | | |
| | Harri Heliövaara | 2 | 2 | | | | |
| | Harri Heliövaara | 2 | 2 | 3 | Matthew Ebden | 6 | 7 |
| | | | | 6 | John-Patrick Smith | 4 | 5 |
| WC | Oscar Manuel Sánchez Hirales | 1 | 2 | 6 | John-Patrick Smith | 4 | 5 |
| 6 | John-Patrick Smith | 6 | 6 | | | | |

#### Fourth qualifier

| First round | First round | First round | First round | First round | Qualifying competition | Qualifying competition | Qualifying competition | Qualifying competition | Qualifying competition |
| 4 | Yosuke Watanuki | 7$^7$ | 4 | 6 | | | | | |
| | Luis Patiño | 6$^3$ | 6 | 2 | | | | | |
| | Luis Patiño | 6$^3$ | 6 | 2 | 4 | Yosuke Watanuki | 5 | 7$^7$ | 5$^r$ |
| | | | | | | Alexander Sarkissian | 7 | 6$^4$ | 5 |
| | Alexander Sarkissian | 6 | 6 | | | Alexander Sarkissian | 7 | 6$^4$ | 5 |
| 8 | Raymond Sarmiento | 4 | 1 | | | | | | |