# 2018 Korea Open – Singles

Jeļena Ostapenko was the defending champion, but lost in the second round to Ekaterina Alexandrova.
Kiki Bertens won the title, defeating Ajla Tomljanović in the final, 7–6$^{(7–2)}$, 4–6, 6–2.
This tournament was the last in Agnieszka Radwańska's career. The former world No. 2 played the final match of her professional career in the second round, when she lost to Irina-Camelia Begu in straight sets.

## Seeds

* Jeļena Ostapenko (second round)
* Kiki Bertens (champion)
* Maria Sakkari (semifinals)
* Magdaléna Rybáriková (first round, retired)
* Alison Van Uytvanck (first round)
* Hsieh Su-wei (semifinals)
* Irina-Camelia Begu (Quarterfinal)
* Kirsten Flipkens (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 |
| 6 | Hsieh Su-wei | 4 | 7 | 4 | | | | | |
| | Ajla Tomljanović | 6 | 5 | 6 | | | | | |
| | Ajla Tomljanović | 6 | 5 | 6 | | Ajla Tomljanović | 6$^2$ | 6 | 2 |
| | | | | | 2 | Kiki Bertens | 7$^7$ | 4 | 6 |
| 3 | Maria Sakkari | 4 | 2 | | 2 | Kiki Bertens | 7$^7$ | 4 | 6 |
| 2 | Kiki Bertens | 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 | Semifinals |
| 1 | J Ostapenko | 6 | 6 | | | | | | | | | | | | | | | | |
| | L Arruabarrena | 3 | 3 | | 1 | J Ostapenko | 3 | 2 | | | | | | | | | | | |
| | J Larsson | 1 | 2 | | | E Alexandrova | 6 | 6 | | | | | | | | | | | |
| | E Alexandrova | 6 | 6 | | | | | | | | E Alexandrova | 0 | 1 | | | | | | |
| WC | J-h Choi | 3 | 6 | 4 | | | | | | 6 | S-w Hsieh | 6 | 6 | | | | | | |
| | S Vögele | 6 | 2 | 6 | | S Vögele | 2 | 1 | | | | | | | | | | | |
| Q | J Teichmann | 6 | 1 | 6$^0$ | 6 | S-w Hsieh | 6 | 6 | | | | | | | | | | | |
| 6 | S-w Hsieh | 2 | 6 | 7$^7$ | | | | | | | | | | | 6 | S-w Hsieh | 4 | 7 | 4 |
| 4 | M Rybáriková | 3 | 2$^r$ | | | | | | | | | | | | | A Tomljanović | 6 | 5 | 6 |
| PR | M Minella | 6 | 3 | | PR | M Minella | 6 | 6 | | | | | | | | | | | |
| Q | P Hon | 3 | 6 | 6 | Q | P Hon | 4 | 3 | | | | | | | | | | | |
| WC | S-j Jang | 6 | 2 | 2 | | | | | | PR | M Minella | 2 | 6 | 5 | | | | | |
| | P Hercog | 1 | 3 | | | | | | | | A Tomljanović | 6 | 4 | 7 | | | | | |
| | T Zidanšek | 6 | 6 | | | T Zidanšek | 6 | 1 | 3 | | | | | | | | | | |
| | A Tomljanović | 3 | 7 | 7 | | A Tomljanović | 2 | 6 | 6 | | | | | | | | | | |
| 5 | A Van Uytvanck | 6 | 5 | 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 |
| 7 | I-C Begu | 7 | 6 | | | | | | | | | | | | | | | |
| Q | M Barthel | 5 | 4 | | 7 | I-C Begu | 6 | 6 | | | | | | | | | | |
| PR | B Mattek-Sands | 4 | 5 | | | A Radwańska | 4 | 3 | | | | | | | | | | |
| | A Radwańska | 6 | 7 | | | | | | | 7 | I-C Begu | 3 | 6 | 4 | | | | |
| Q | V Flink | 5 | 4 | | | | | | | 3 | M Sakkari | 6 | 4 | 6 | | | | |
| PR | M Gasparyan | 7 | 6 | | PR | M Gasparyan | 2 | 2 | | | | | | | | | | |
| | AK Schmiedlová | 0 | 1 | | 3 | M Sakkari | 6 | 6 | | | | | | | | | | |
| 3 | M Sakkari | 6 | 6 | | | | | | | | | | | | 3 | M Sakkari | 4 | 2 |
| 8 | K Flipkens | 6 | 6 | | | | | | | | | | | | 2 | K Bertens | 6 | 6 |
| WC | S-h Park | 0 | 2 | | 8 | K Flipkens | 4 | 6 | 5 | | | | | | | | | |
| | E Rodina | 6 | 6 | | | E Rodina | 6 | 4 | 7 | | | | | | | | | |
| Q | D Radanović | 1 | 1 | | | | | | | | E Rodina | 6 | 3 | 0 | | | | |
| | D Jakupović | 3 | 6 | 6 | | | | | | 2 | K Bertens | 3 | 6 | 6 | | | | |
| Q | N-l Han | 6 | 4 | 3 | | D Jakupović | 4 | 5 | | | | | | | | | | |
| | L Kumkhum | 6$^7$ | 2 | | 2 | K Bertens | 6 | 7 | | | | | | | | | | |
| 2 | K Bertens | 7$^9$ | 6 | | | | | | | | | | | | | | | |

## Qualifying
### Seeds

* Mona Barthel (qualified)
* Arantxa Rus (qualifying competition)
* Jil Teichmann (qualified)
* Arina Rodionova (first round)
* Harriet Dart (first round)
* Priscilla Hon (qualified)
* Sílvia Soler Espinosa (qualifying competition)
* Bibiane Schoofs (qualifying competition)
* Jaimee Fourlis (first round)
* Dejana Radanović (qualified)
* Varvara Flink (qualified)
* Nina Stojanović (first round)

### Qualifiers

* Mona Barthel
* Varvara Flink
* Jil Teichmann
* Dejana Radanović
* Han Na-lae
* Priscilla Hon

### Qualifying draw
#### First qualifier

| First round | First round | First round | First round | Qualifying competition | Qualifying competition | Qualifying competition | Qualifying competition |
| 1 | Mona Barthel | 6 | 6 | | | | |
| WC | Hanna Chang | 1 | 3 | | | | |
| WC | Hanna Chang | 1 | 3 | 1 | Mona Barthel | 6 | 6 |
| | | | | 7 | Sílvia Soler Espinosa | 3 | 4 |
| | Peangtarn Plipuech | 3 | 0 | 7 | Sílvia Soler Espinosa | 3 | 4 |
| 7 | Sílvia Soler Espinosa | 6 | 6 | | | | |

#### Second qualifier

| First round | First round | First round | First round | First round | Qualifying competition | Qualifying competition | Qualifying competition | Qualifying competition | Qualifying competition |
| 2 | Arantxa Rus | 6 | 7$^8$ | | | | | | |
| WC | Kim Da-bin | 2 | 6$^6$ | | | | | | |
| WC | Kim Da-bin | 2 | 6$^6$ | | 2 | Arantxa Rus | 1 | 6 | 6$^6$ |
| | | | | | 11 | Varvara Flink | 6 | 3 | 7$^8$ |
| WC | Jeong Su-nam | 2 | 6 | 0 | 11 | Varvara Flink | 6 | 3 | 7$^8$ |
| 11 | Varvara Flink | 6 | 3 | 6 | | | | | |

#### Third qualifier

| First round | First round | First round | First round | Qualifying competition | Qualifying competition | Qualifying competition | Qualifying competition | Qualifying competition |
| 3 | Jil Teichmann | 6 | 6 | | | | | |
| | Amandine Hesse | 4 | 0 | | | | | |
| | Amandine Hesse | 4 | 0 | 3 | Jil Teichmann | 6 | 4 | 7 |
| | | | | 8 | Bibiane Schoofs | 4 | 6 | 5 |
| | Ellen Perez | 0 | 4 | 8 | Bibiane Schoofs | 4 | 6 | 5 |
| 8 | Bibiane Schoofs | 6 | 6 | | | | | |

#### Fourth qualifier

| First round | First round | First round | First round | First round | Qualifying competition | Qualifying competition | Qualifying competition | Qualifying competition |
| 4 | Arina Rodionova | 7$^7$ | 0 | 2 | | | | |
| | Mai Minokoshi | 6$^3$ | 6 | 6 | | | | |
| | Mai Minokoshi | 6$^3$ | 6 | 6 | | Mai Minokoshi | 1 | 4 |
| | | | | | 10 | Dejana Radanović | 6 | 6 |
| WC | Lee So-ra | 6 | 2 | 1 | 10 | Dejana Radanović | 6 | 6 |
| 10 | Dejana Radanović | 2 | 6 | 6 | | | | |

#### Fifth qualifier

| First round | First round | First round | First round | First round | Qualifying competition | Qualifying competition | Qualifying competition | Qualifying competition |
| 5 | Harriet Dart | 6 | 1 | 5 | | | | |
| | Han Na-lae | 0 | 6 | 7 | | | | |
| | Han Na-lae | 0 | 6 | 7 | | Han Na-lae | 7 | 6 |
| | | | | | PR | Barbora Štefková | 5 | 3 |
| PR | Barbora Štefková | 6 | 6 | | PR | Barbora Štefková | 5 | 3 |
| 12 | Nina Stojanović | 1 | 1 | | | | | |

#### Sixth qualifier

| First round | First round | First round | First round | First round | Qualifying competition | Qualifying competition | Qualifying competition | Qualifying competition |
| 6 | Priscilla Hon | 6 | 6 | | | | | |
| | Zhang Yuxuan | 4 | 4 | | | | | |
| | Zhang Yuxuan | 4 | 4 | | 6 | Priscilla Hon | 7$^7$ | 6 |
| | | | | | | Katy Dunne | 6$^5$ | 2 |
| | Katy Dunne | 2 | 6 | 6 | | Katy Dunne | 6$^5$ | 2 |
| 9 | Jaimee Fourlis | 6 | 2 | 2 | | | | |