# 2021 Puerto Vallarta Open – Singles

Sebastian Ofner was the defending champion but chose not to defend his title.
Daniel Altmaier won the title after defeating Alejandro Tabilo 6–3, 3–6, 6–3 in the final.

## Seeds

* Pablo Cuevas (quarterfinals, retired)
* Daniel Altmaier (champion)
* Alejandro Tabilo (final)
* Ernesto Escobedo (first round)
* Michael Mmoh (semifinals)
* Christian Harrison (second round)
* Wu Tung-lin (second round)
* Tatsuma Ito (quarterfinals)

## 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 | Final |
| | Yosuke Watanuki | 3 | 2 | | | | | |
| 3 | Alejandro Tabilo | 6 | 6 | | | | | |
| 3 | Alejandro Tabilo | 6 | 6 | 3 | Alejandro Tabilo | 3 | 6 | 3 |
| | | | | 2 | Daniel Altmaier | 6 | 3 | 6 |
| 5 | Michael Mmoh | 4 | 2 | 2 | Daniel Altmaier | 6 | 3 | 6 |
| 2 | Daniel Altmaier | 6 | 6 | | | | | |

### 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 | Quarterfinals | Semifinals | Semifinals | Semifinals | Semifinals |
| 1 | P Cuevas | 7 | 6 | | | | | | | | | | | | | | | |
| | A Kovacevic | 5 | 4 | | 1 | P Cuevas | 7$^7$ | 0 | | | | | | | | | | |
| Alt | MF Descotte | 6$^2$ | 7 | 6 | Alt | MF Descotte | 6$^3$ | 0$^r$ | | | | | | | | | | |
| WC | G López Villaseñor | 7$^7$ | 5 | 0 | | | | | | 1 | P Cuevas | 6 | 4 | 0$^r$ | | | | |
| | Yo Watanuki | 6 | 6 | | | | | | | | Yo Watanuki | 4 | 6 | 2 | | | | |
| PR | R Statham | 3 | 2 | | | Yo Watanuki | 6$^5$ | 7 | 6 | | | | | | | | | |
| Q | L Draxl | 3 | 1 | | 7 | T-l Wu | 7$^7$ | 5 | 3 | | | | | | | | | |
| 7 | T-l Wu | 6 | 6 | | | | | | | | | | | | | Yo Watanuki | 3 | 2 |
| 3 | A Tabilo | 6 | 6 | | | | | | | | | | | | 3 | A Tabilo | 6 | 6 |
| | A Menéndez Maceiras | 3 | 2 | | 3 | A Tabilo | 6 | 6 | | | | | | | | | | |
| WC | Milledge Cossu | 1 | 3 | | | D Young | 2 | 1 | | | | | | | | | | |
| | D Young | 6 | 6 | | | | | | | 3 | A Tabilo | 6 | 6 | | | | | |
| | A Rybakov | 7 | 4$^r$ | | | | | | | 8 | T Ito | 2 | 2 | | | | | |
| Q | A Hernández | 5 | 4 | | Q | A Hernández | 2 | 3 | | | | | | | | | | |
| | G Brouwer | 2 | 6$^3$ | | 8 | T Ito | 6 | 6 | | | | | | | | | | |
| 8 | T Ito | 6 | 7$^7$ | | | | | | | | | | | | | | | |

### 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 | M Mmoh | 6 | 6 | | | | | | | | | | | | | | | |
| | N Chappell | 2 | 3 | | 5 | M Mmoh | 7 | 4 | 6 | | | | | | | | | |
| WC | J Shang | 6 | 6 | | WC | J Shang | 5 | 6 | 4 | | | | | | | | | |
| Alt | M Cuevas | 4 | 4 | | | | | | | 5 | M Mmoh | 7$^9$ | 6 | | | | | |
| | K Uchida | 6 | 6 | | | | | | | | K Uchida | 6$^7$ | 3 | | | | | |
| PR | A Sarkissian | 3 | 4 | | | K Uchida | 6 | 6 | | | | | | | | | | |
| | A Galarneau | 7 | 6$^4$ | 7 | | A Galarneau | 4 | 2 | | | | | | | | | | |
| 4 | E Escobedo | 5 | 7$^7$ | 5 | | | | | | | | | | | 5 | M Mmoh | 4 | 2 |
| 6 | C Harrison | 6 | 6 | | | | | | | | | | | | 2 | D Altmaier | 6 | 6 |
| | R Ortega Olmedo | 4 | 0 | | 6 | C Harrison | 1 | 6$^9$ | | | | | | | | | | |
| Q | Christian Langmo | 7 | 4 | 5 | | Z Svajda | 6 | 7$^{11}$ | | | | | | | | | | |
| | Z Svajda | 5 | 6 | 7 | | | | | | | Z Svajda | 6 | 6$^8$ | 3 | | | | |
| Q | G Nanda | 6 | 6 | | | | | | | 2 | D Altmaier | 4 | 7$^{10}$ | 6 | | | | |
| | JC Aragone | 2 | 0 | | Q | G Nanda | 3 | 3 | | | | | | | | | | |
| | Mi Redlicki | 6$^5$ | 1 | | 2 | D Altmaier | 6 | 6 | | | | | | | | | | |
| 2 | D Altmaier | 7$^7$ | 6 | | | | | | | | | | | | | | | |