| Singles | |
|---|---|
| 2021 Internazionali di Tennis Città di Todi | |
| Champion |  Mario Vilella Martínez |
| Runner-up |  Federico Gaio |
| Score | 7–6(7–3), 1–6, 6–3 |
Yannick Hanfmann was the defending champion [1] but chose not to defend his title.
Mario Vilella Martínez won the title after defeating Federico Gaio 7–6(7–3), 1–6, 6–3 in the final.
Federico Gaio (final) Mario Vilella Martínez (champion)
Dmitry Popko (second round)
Tomás Martín Etcheverry (semifinals) Renzo Olivo (first round) Andrea Collarini (second round) Gian Marco Moroni (first round) Lorenzo Giustino (first round)| Semifinals | Final | ||||||||||||
| 1 | Federico Gaio | 6 | 6 | ||||||||||
| 4 | Tomás Martín Etcheverry | 2 | 2 | ||||||||||
| 1 | Federico Gaio | 63 | 6 | 3 | |||||||||
| 2 | Mario Vilella Martínez | 77 | 1 | 6 | |||||||||
| Q |  Matheus Pucinelli de Almeida | 64 | 6 | 1 | |||||||||
| 2 | Mario Vilella Martínez | 77 | 3 | 6 | |||||||||
| First round | Second round | Quarterfinals | Semifinals | ||||||||||||||||||||||||
| 1 | F Gaio | 6 | 6 | ||||||||||||||||||||||||
| PR |  V Galović | 3 | 2 | 1 | F Gaio | 61 | 6 | 77 | |||||||||||||||||||
| Alt |  S Mansouri | 3 | 2 | TA Tirante | 77 | 1 | 62 | ||||||||||||||||||||
| TA Tirante | 6 | 6 | 1 | F Gaio | 7 | 6 | |||||||||||||||||||||
| WC | F Cobolli | 3 | 6 | 6 | WC | F Cobolli | 5 | 4 | |||||||||||||||||||
| P Sakamoto | 6 | 4 | 3 | WC | F Cobolli | 6 | 6 | ||||||||||||||||||||
 J Domingues | 2 | 3 | 6 | A Collarini | 4 | 3 | |||||||||||||||||||||
| 6 | A Collarini | 6 | 6 | 1 | F Gaio | 6 | 6 | ||||||||||||||||||||
| 4 | TM Etcheverry | 6 | 77 | 4 | TM Etcheverry | 2 | 2 | ||||||||||||||||||||
| M Viola | 4 | 64 | 4 | TM Etcheverry | 2 | 6 | 4 | ||||||||||||||||||||
| J Ocleppo | 3 | 6 | 4 | Q | M Arnaldi | 6 | 3 | 1r | |||||||||||||||||||
| Q | M Arnaldi | 6 | 1 | 6 | 4 | TM Etcheverry | 6 | 6 | |||||||||||||||||||
| A Arnaboldi | 1 | 64 |  A Ritschard | 1 | 1 | ||||||||||||||||||||||
| A Ritschard | 6 | 77 | A Ritschard | 6 | 6 | ||||||||||||||||||||||
| Q | G Fonio | 6 | 6 | Q | G Fonio | 3 | 4 | ||||||||||||||||||||
| 8 | L Giustino | 4 | 3 | ||||||||||||||||||||||||
| First round | Second round | Quarterfinals | Semifinals | ||||||||||||||||||||||||
| 7 | GM Moroni | 0 | 3 | ||||||||||||||||||||||||
 N Jarry | 6 | 6 | N Jarry | 4 | 6 | 7 | |||||||||||||||||||||
| P Cachin | 6 | 6 | P Cachin | 6 | 4 | 5 | |||||||||||||||||||||
| Alt | F Díaz Acosta | 3 | 4 | N Jarry | 6 | 3 | 1 | ||||||||||||||||||||
| F Baldi | 6 | 4 | 1 | Q | M Pucinelli de Almeida | 3 | 6 | 6 | |||||||||||||||||||
| Q | M Pucinelli de Almeida | 1 | 6 | 6 | Q | M Pucinelli de Almeida | 3 | 6 | 6 | ||||||||||||||||||
| WC | F Passaro | 7 | 2 | 2 | 3 | D Popko | 6 | 1 | 2 | ||||||||||||||||||
| 3 | D Popko | 5 | 6 | 6 | Q | M Pucinelli de Almeida | 64 | 6 | 1 | ||||||||||||||||||
| 5 | R Olivo | 65 | 4 | 2 | M Vilella Martínez | 77 | 3 | 6 | |||||||||||||||||||
| Q |  A Cazaux | 77 | 6 | Q | A Cazaux | 3 | 3 | ||||||||||||||||||||
| A Pellegrino | 62 | 64 | G Zeppieri | 6 | 6 | ||||||||||||||||||||||
| G Zeppieri | 77 | 77 | G Zeppieri | 3 | 3 | ||||||||||||||||||||||
| WC | F Forti | 6 | 65 | 6 | 2 | M Vilella Martínez | 6 | 6 | |||||||||||||||||||
| LL | F Agamenone | 2 | 77 | 3 | WC | F Forti | 3 | 1 | |||||||||||||||||||
| T Lamasine | 2 | 64 | 2 | M Vilella Martínez | 6 | 6 | |||||||||||||||||||||
| 2 | M Vilella Martínez | 6 | 77 | ||||||||||||||||||||||||
Víctor Estrella Burgos was the two-time defending champion and successfully defended his title, defeating Paolo Lorenzi in the final, 6–7(2–7), 7–5, 7–6(8–6).
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Federico Delbonis was the defending champion but chose not to defend his title.
Cristian Garín was the defending champion but chose not to defend his title.
Cristian Garín was the defending champion but chose not to defend his title.
Guido Andreozzi was the defending champion but chose not to defend his title.
Guido Pella was the defending champion but chose not to defend his title.
Mikael Ymer was the defending champion but chose not to defend his title.
Juan Ignacio Londero was the defending champion, but lost to Laslo Đere in the quarterfinals.
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Laslo Đere was the defending champion, but withdrew with an abdominal injury before the tournament began.
Dominic Thiem was the defending champion and chose not to defend his title, as he was still competing at the 2020 US Open.
Cristian Garín was the defending champion, but chose not to defend his title.
Cristian Garín defeated Facundo Bagnis in the final, 6–4, 6–7(3–7), 7–5 to capture the men's singles tennis title at the 2021 Chile Open.
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Marcelo Arévalo and Miguel Ángel Reyes-Varela were the defending champions but chose not to defend their title.
Casper Ruud defeated the defending champion Diego Schwartzman in the final, 5–7, 6–2, 6–3 to win the singles title at the 2022 Argentina Open.
Mario Vilella Martínez was the defending champion but chose not to defend his title.