| Singles | |
|---|---|
| 2018 Challenger La Manche | |
| Champion |  Maximilian Marterer |
| Runner-up |  Constant Lestienne |
| Final score | 6–4, 7–5 |
Mathias Bourgue was the defending champion but lost in the second round to Constant Lestienne.
Maximilian Marterer won the title after defeating Lestienne 6–4, 7–5 in the final.
Gilles Simon (second round) Maximilian Marterer (champion)
Malek Jaziri (second round)
Matteo Berrettini (semifinals) Oscar Otte (second round)
Norbert Gombos (first round) Kenny de Schepper (quarterfinals) Calvin Hemery (first round)| Semifinals | Final | ||||||||||||
| Mats Moraing | 3 | 4 | |||||||||||
| WC | Constant Lestienne | 6 | 6 | ||||||||||
| WC | Constant Lestienne | 4 | 5 | ||||||||||
| 2 | Maximilian Marterer | 6 | 7 | ||||||||||
| 4 | Matteo Berrettini | 4 | 67 | ||||||||||
| 2 | Maximilian Marterer | 6 | 79 | ||||||||||
| First round | Second round | Quarterfinals | Semifinals | ||||||||||||||||||||||||
| 1 | G Simon | 6 | 77 | ||||||||||||||||||||||||
| B Bonzi | 4 | 65 | 1 | G Simon | 4 | 4 | |||||||||||||||||||||
 G Oliveira | 5 | 62 | M Moraing | 6 | 6 | ||||||||||||||||||||||
| M Moraing | 7 | 77 | M Moraing | 6 | 6 | ||||||||||||||||||||||
| WC | A Hoang | 6 | 4 | 67 | Q |  M Ymer | 2 | 2 | |||||||||||||||||||
| Q | M Ymer | 3 | 6 | 79 | Q | M Ymer | 6 | 6 | |||||||||||||||||||
| G Sakharov | 6 | 6 | G Sakharov | 4 | 4 | ||||||||||||||||||||||
| 8 | C Hemery | 2 | 1 | M Moraing | 3 | 4 | |||||||||||||||||||||
| 3/Alt | M Jaziri | 6 | 6 | WC | C Lestienne | 6 | 6 | ||||||||||||||||||||
| WC | G Blancaneaux | 4 | 4 | 3/Alt | M Jaziri | 68 | 2 | ||||||||||||||||||||
| T Kamke | 77 | 6 | T Kamke | 710 | 6 | ||||||||||||||||||||||
 V Šafránek | 61 | 4 | T Kamke | 3 | 6 | 3 | |||||||||||||||||||||
| WC | C Lestienne | 6 | 6 | WC | C Lestienne | 6 | 4 | 6 | |||||||||||||||||||
 D Novak | 1 | 2 | WC | C Lestienne | 6 | 1 | 6 | ||||||||||||||||||||
| M Bourgue | 6 | 6 | M Bourgue | 2 | 6 | 3 | |||||||||||||||||||||
| 6 | N Gombos | 3 | 4 | ||||||||||||||||||||||||
| First round | Second round | Quarterfinals | Semifinals | ||||||||||||||||||||||||
| 7 | K de Schepper | 6 | 3 | 6 | |||||||||||||||||||||||
| WC | C Denolly | 3 | 6 | 4 | 7 | K de Schepper | w/o | ||||||||||||||||||||
 C Taberner | 1 | 1 |  A Vatutin | ||||||||||||||||||||||||
| A Vatutin | 6 | 6 | 7 | K de Schepper | 4 | 5 | |||||||||||||||||||||
| A Pavlásek | 6 | 2 | 6 | 4 | M Berrettini | 6 | 7 | ||||||||||||||||||||
| Q | R Boutillier | 4 | 6 | 4 | A Pavlásek | 3 | 63 | ||||||||||||||||||||
| LL | Maxime Tabatruong | 77 | 5 | 4 | 4 | M Berrettini | 6 | 77 | |||||||||||||||||||
| 4 | M Berrettini | 63 | 7 | 6 | 4 | M Berrettini | 4 | 67 | |||||||||||||||||||
| 5 | O Otte | 6 | 6 | 2 | M Marterer | 6 | 79 | ||||||||||||||||||||
| Q |  J Clarke | 2 | 2 | 5 | O Otte | 4 | 6 | 3 | |||||||||||||||||||
 K Majchrzak | 3 | 1r | Q |  A Popyrin | 6 | 3 | 6 | ||||||||||||||||||||
| Q | A Popyrin | 6 | 2 | Q | A Popyrin | 2 | 4 | ||||||||||||||||||||
 T Brkić | 62 | 2 | 2 | M Marterer | 6 | 6 | |||||||||||||||||||||
| L Vanni | 77 | 6 | L Vanni | 4 | 3 | ||||||||||||||||||||||
| J Munar | 3 | 64 | 2 | M Marterer | 6 | 6 | |||||||||||||||||||||
| 2 | M Marterer | 6 | 77 | ||||||||||||||||||||||||
Tomáš Berdych was the defending champion and successfully defended his title, defeating Jack Sock in the final, 7–6(7–1), 6–2.
Viktor Troicki was the defending champion and successfully defended his title, defeating Grigor Dimitrov in the final, 2–6, 6–1, 7–6(9–7).
Daniel Muñoz de la Nava was the defending champion but chose not to defend his title.
Roberto Carballés Baena was the defending champion but retired in the second round facing Maximilian Marterer.
Roberto Bautista Agut was the defending champion, but lost in the semifinals to David Goffin.
Thomas Fabbiano was the defending champion but lost to Evgeny Donskoy 6–3, 6–4 in the final.
Elias Ymer was the defending champion but lost in the first round to Lukáš Rosol.
This was the first edition of the tournament.
Dominic Thiem was the defending champion, but chose not to participate this year.
Florian Mayer was the defending champion, but lost to Roger Federer in the quarterfinals.
Albert Ramos Viñolas was the defending champion, but lost in the quarterfinals to Fernando Verdasco.
Paolo Lorenzi was the defending champion, but lost in the second round to João Sousa.
Grigor Dimitrov defeated Nick Kyrgios in the final, 6–3, 7–5, to win the 2017 Cincinnati Masters. It was his first ATP World Tour Masters 1000 title, and he did not lose a set throughout the tournament.
Adam Pavlásek was the defending champion but chose not to defend his title.
Ernesto Escobedo was the defending champion but lost in the first round to Mats Moraing.
Steve Darcis was the defending champion but chose not to defend his title.
Andrey Rublev was the defending champion, but lost in the quarterfinals to Robin Haase. This was Rublev's first tournament back on tour after missing three months due to a stress fracture in his back.
Roberto Bautista Agut was the defending champion, but withdrew before the tournament began.
Maximilian Marterer was the defending champion but lost in the first round to Filip Horanský.
Casper Ruud defeated Hugo Gaston in the final, 6–3, 6–2, to win the men's singles tennis title at the 2021 Swiss Open.