# 2018 Open de Rennes – Singles

Uladzimir Ignatik was the defending champion but lost in the first round to Alexey Vatutin.
Vasek Pospisil won the title after defeating Ričardas Berankis 6–1, 6–2 in the final.

## Seeds

* Mikhail Youzhny (second round)
* Vasek Pospisil (champion)
* Gastão Elias (first round)
* Sergiy Stakhovsky (first round)
* Dustin Brown (first round)
* Quentin Halys (quarterfinals)
* Ričardas Berankis (final)
* Norbert Gombos (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 | Final | Final | Final | Final |
| 7/Alt | Ričardas Berankis | 7 | 6 | | | | |
| | Liam Broady | 5 | 1 | | | | |
| | Liam Broady | 5 | 1 | 7/Alt | Ričardas Berankis | 1 | 2 |
| | | | | 2 | Vasek Pospisil | 6 | 6 |
| Q | Antoine Hoang | 4 | 6$^4$ | 2 | Vasek Pospisil | 6 | 6 |
| 2 | Vasek Pospisil | 6 | 7$^7$ | | | | |

### 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 | M Youzhny | 6 | 6 | | | | | | | | | | | | | | | |
| | C Moutet | 1 | 2 | | 1 | M Youzhny | 4 | 1 | | | | | | | | | | |
| | G Sakharov | 6 | 4 | 6 | | G Sakharov | 6 | 6 | | | | | | | | | | |
| WC | U Humbert | 3 | 6 | 3 | | | | | | | G Sakharov | 1 | 6 | 4 | | | | |
| | S Bolelli | 6 | 7$^7$ | | | | | | | 7/Alt | R Berankis | 6 | 4 | 6 | | | | |
| | S Ofner | 2 | 6$^1$ | | | S Bolelli | 5 | 3 | | | | | | | | | | |
| | M Bourgue | 3 | 4 | | 7/Alt | R Berankis | 7 | 6 | | | | | | | | | | |
| 7/Alt | R Berankis | 6 | 6 | | | | | | | | | | | | 7/Alt | R Berankis | 7 | 6 |
| 3 | G Elias | 1 | 4 | | | | | | | | | | | | | L Broady | 5 | 1 |
| WC | M Guinard | 6 | 6 | | WC | M Guinard | 3 | 6 | 6 | | | | | | | | | |
| Q | M Ymer | 7$^7$ | 5 | 2 | WC | E Gulbis | 6 | 3 | 4 | | | | | | | | | |
| WC | E Gulbis | 6$^4$ | 7 | 6 | | | | | | WC | M Guinard | 4 | 4 | | | | | |
| WC | M Janvier | 7$^7$ | 6 | | | | | | | | L Broady | 6 | 6 | | | | | |
| | T Robredo | 6$^5$ | 4 | | WC | M Janvier | 4 | 1 | | | | | | | | | | |
| | L Broady | 6 | 4 | 7 | | L Broady | 6 | 6 | | | | | | | | | | |
| 5 | D Brown | 3 | 6 | 5 | | | | | | | | | | | | | | |

### 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 |
| 8 | N Gombos | 6 | 6 | | | | | | | | | | | | | | | |
| | K de Schepper | 2 | 3 | | 8 | N Gombos | 2 | 6 | 3 | | | | | | | | | |
| | A De Greef | 6$^7$ | 6 | 3 | Q | A Hoang | 6 | 4 | 6 | | | | | | | | | |
| Q | A Hoang | 7$^9$ | 3 | 6 | | | | | | Q | A Hoang | 6 | 3 | 6 | | | | |
| | N Milojević | 7$^7$ | 2 | 4 | | | | | | | Y Maden | 3 | 6 | 2 | | | | |
| | Y Maden | 6$^5$ | 6 | 6 | | Y Maden | 6 | 6 | | | | | | | | | | |
| | E Ymer | 6 | 3 | 6 | | E Ymer | 4 | 4 | | | | | | | | | | |
| 4 | S Stakhovsky | 1 | 6 | 3 | | | | | | | | | | | Q | A Hoang | 4 | 6$^4$ |
| 6 | Q Halys | 6 | 7$^7$ | | | | | | | | | | | | 2 | V Pospisil | 6 | 7$^7$ |
| Q | T Lamasine | 1 | 6$^5$ | | 6 | Q Halys | 4 | 6 | 7$^{10}$ | | | | | | | | | |
| | A Vatutin | 6 | 6 | | | A Vatutin | 6 | 4 | 6$^8$ | | | | | | | | | |
| | U Ignatik | 1 | 4 | | | | | | | 6 | Q Halys | 1 | 4 | | | | | |
| SE | M Moraing | 6$^5$ | 6 | 6 | | | | | | 2 | V Pospisil | 6 | 6 | | | | | |
| | C Hemery | 7$^7$ | 1 | 4 | SE | M Moraing | 6$^4$ | 6$^0$ | | | | | | | | | | |
| Q | Y Uchiyama | 3 | 4 | | 2 | V Pospisil | 7$^7$ | 7$^7$ | | | | | | | | | | |
| 2 | V Pospisil | 6 | 6 | | | | | | | | | | | | | | | |