# 2021 Tampere Open – Singles

Mikael Ymer was the defending champion but chose not to defend his title.
Jiří Lehečka won the title after defeating Nicolás Kicker 5–7, 6–4, 6–3 in the final.

## Seeds

* Botic van de Zandschulp (semifinals)
* Henri Laaksonen (withdrew)
* Antoine Hoang (first round)
* Mario Vilella Martínez (quarterfinals)
* Dmitry Popko (quarterfinals)
* Kimmer Coppejans (first round)
* Alexandre Müller (second round)
* Guido Andreozzi (second 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 | Semifinals | Final | Final | Final | Final | Final |
| 1 | Botic van de Zandschulp | 3 | 6 | 3 | | | | | |
| Q | Nicolás Kicker | 6 | 3 | 6 | | | | | |
| Q | Nicolás Kicker | 6 | 3 | 6 | Q | Nicolás Kicker | 7 | 4 | 3 |
| | | | | | | Jiří Lehečka | 5 | 6 | 6 |
| | Jiří Lehečka | 6 | 6 | | | Jiří Lehečka | 5 | 6 | 6 |
| LL | Kyrian Jacquet | 3 | 0 | | | | | | |

### 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 | Semifinals |
| 1 | B van de Zandschulp | 4 | 6 | 6 | | | | | | | | | | | | | | |
| | R Bonadio | 6 | 2 | 2 | 1 | B van de Zandschulp | 6 | 6 | | | | | | | | | | |
| | JC Aragone | 4 | 4 | | | P Krstin | 3 | 1 | | | | | | | | | | |
| | P Krstin | 6 | 6 | | | | | | | 1 | B van de Zandschulp | 6 | 7$^7$ | | | | | |
| | A Arnaboldi | 6 | 6 | | | | | | | 5 | D Popko | 4 | 6$^0$ | | | | | |
| | F Meligeni Alves | 1 | 4 | | | A Arnaboldi | 4 | 3 | | | | | | | | | | |
| Alt | O Luz | 6$^5$ | 5 | | 5 | D Popko | 6 | 6 | | | | | | | | | | |
| 5 | D Popko | 7$^7$ | 7 | | | | | | | | | | | 1 | B van de Zandschulp | 3 | 6 | 3 |
| 4/SE | M Vilella Martínez | 4 | 7$^7$ | 7 | | | | | | | | | | Q | N Kicker | 6 | 3 | 6 |
| | J Domingues | 6 | 6$^5$ | 5 | 4/SE | M Vilella Martínez | 7 | 6 | | | | | | | | | | |
| Q | B Bobrov | 1 | 5 | | | P Cachin | 5 | 4 | | | | | | | | | | |
| | P Cachin | 6 | 7 | | | | | | | 4/SE | M Vilella Martínez | 6$^6$ | 0 | | | | | |
| Q | N Kicker | 6 | 6 | | | | | | | Q | N Kicker | 7$^8$ | 6 | | | | | |
| WC | Leo Borg | 3 | 0 | | Q | N Kicker | 6 | 3 | 6 | | | | | | | | | |
| WC | P Niklas-Salminen | 2 | 1 | | 7 | A Müller | 4 | 6 | 2 | | | | | | | | | |
| 7 | A Müller | 6 | 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 | Semifinals | Semifinals | Semifinals | Semifinals |
| 8 | G Andreozzi | 6 | 6 | | | | | | | | | | | | | | |
| | M Moraing | 4 | 1 | | 8 | G Andreozzi | 2 | 4 | | | | | | | | | |
| Q | A Cazaux | 6 | 6$^5$ | 2 | WC | O Virtanen | 6 | 6 | | | | | | | | | |
| WC | O Virtanen | 3 | 7$^7$ | 6 | | | | | | WC | O Virtanen | 4 | 1 | | | | |
| | N Jarry | 6$^3$ | 6 | 6 | | | | | | | J Lehečka | 6 | 6 | | | | |
| Alt | J Forejtek | 7$^7$ | 3 | 3 | | N Jarry | 4 | 4 | | | | | | | | | |
| | J Lehečka | 6 | 6 | | | J Lehečka | 6 | 6 | | | | | | | | | |
| 3 | A Hoang | 1 | 4 | | | | | | | | | | | | J Lehečka | 6 | 6 |
| 6 | K Coppejans | 6 | 3 | 6$^6$ | | | | | | | | | | LL | K Jacquet | 3 | 0 |
| | D Kuzmanov | 1 | 6 | 7$^8$ | | D Kuzmanov | 6 | 4 | 6$^5$ | | | | | | | | |
| LL | K Jacquet | 2 | 6 | 3 | LL | K Jacquet | 3 | 6 | 7$^7$ | | | | | | | | |
| | G Oliveira | 6 | 1 | 0$^r$ | | | | | | LL | K Jacquet | 6 | 6 | | | | |
| Q | G Blancaneaux | 6 | 7 | | | | | | | Q | G Blancaneaux | 3 | 3 | | | | |
| | F Mena | 4 | 5 | | Q | G Blancaneaux | 6 | 4 | 6 | | | | | | | | |
| | G Elias | 4 | 6 | 5 | LL | A Erler | 3 | 6 | 2 | | | | | | | | |
| LL | A Erler | 6 | 3 | 7 | | | | | | | | | | | | | |