# 2019 Japan Women's Open – Singles

Hsieh Su-wei was the defending champion, but lost to Nao Hibino in the quarterfinals.
Hibino went on to win the title, defeating Misaki Doi in the final, 6–3, 6–2.

## Seeds

* Hsieh Su-wei (quarterfinals)
* Veronika Kudermetova (semifinals)
* Alison Van Uytvanck (quarterfinals)
* Anastasia Potapova (first round)
* Tatjana Maria (first round)
* Zarina Diyas (second round, retired)
* Sara Sorribes Tormo (quarterfinals)
* Laura Siegemund (quarterfinals)

## 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 |
| | Nao Hibino | 4 | 6 | 6 | | | |
| | Mihaela Buzărnescu | 6 | 0 | 3 | | | |
| | Mihaela Buzărnescu | 6 | 0 | 3 | Nao Hibino | 6 | 6 |
| | | | | | Misaki Doi | 3 | 2 |
| | Misaki Doi | 6 | 6 | | Misaki Doi | 3 | 2 |
| 2 | Veronika Kudermetova | 4 | 3 | | | | |

### 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 |
| 1 | S-w Hsieh | 6 | 3 | 6 | | | | | | | | | | | | | |
| WC | R Ozaki | 1 | 6 | 3 | 1 | S-w Hsieh | 1 | 7$^7$ | 7 | | | | | | | | |
| | K Kawa | 0 | 6 | 4 | | P Hon | 6 | 6$^2$ | 5 | | | | | | | | |
| | P Hon | 6 | 1 | 6 | | | | | | 1 | S-w Hsieh | 4 | 3 | | | | |
| Q | LA Fernandez | 7$^7$ | 6$^5$ | 5 | | | | | | | N Hibino | 6 | 6 | | | | |
| | N Hibino | 6$^2$ | 7$^7$ | 7 | | N Hibino | 6 | 3 | | | | | | | | | |
| | D Kovinić | 2 | 2 | | 6 | Z Diyas | 1 | 2$^r$ | | | | | | | | | |
| 6 | Z Diyas | 6 | 6 | | | | | | | | | | | N Hibino | 4 | 6 | 6 |
| 3 | A Van Uytvanck | 6 | 6 | | | | | | | | | | | M Buzărnescu | 6 | 0 | 3 |
| | Y Bonaventure | 4 | 2 | | 3 | A Van Uytvanck | 6 | 3 | 6 | | | | | | | | |
| | L Samsonova | 6$^2$ | 4 | | | K Flipkens | 2 | 6 | 3 | | | | | | | | |
| | K Flipkens | 7$^7$ | 6 | | | | | | | 3 | A Van Uytvanck | 4 | 5 | | | | |
| | M Buzărnescu | 6 | 6 | | | | | | | | M Buzărnescu | 6 | 7 | | | | |
| Q | V Tomova | 1 | 4 | | | M Buzărnescu | 7$^7$ | 7 | | | | | | | | | |
| WC | K Nara | 6 | 6 | | WC | K Nara | 6$^1$ | 5 | | | | | | | | | |
| 5 | T Maria | 4 | 4 | | | | | | | | | | | | | | |

### 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 | S Sorribes Tormo | 6 | 3 | 6 | | | | | | | | | | | | | | |
| | S Cîrstea | 2 | 6 | 2 | 7 | S Sorribes Tormo | 6 | 6 | | | | | | | | | | |
| | V Flink | 6 | 6 | | | V Flink | 3 | 1 | | | | | | | | | | |
| | K Kučová | 3 | 2 | | | | | | | 7 | S Sorribes Tormo | 5 | 1 | | | | | |
| | M Doi | 4 | 7 | 6 | | | | | | | M Doi | 7 | 6 | | | | | |
| Q | J Namigata | 6 | 5 | 2 | | M Doi | 6 | 1 | 6 | | | | | | | | | |
| Q | Z Hives | 6$^4$ | 6 | 6 | Q | Z Hives | 1 | 6 | 3 | | | | | | | | | |
| 4 | A Potapova | 7$^7$ | 4 | 4 | | | | | | | | | | | | M Doi | 6 | 6 |
| 8 | L Siegemund | 6 | 6 | | | | | | | | | | | | 2 | V Kudermetova | 4 | 3 |
| Q | V Savinykh | 4 | 1 | | 8 | L Siegemund | 6 | 5 | 7 | | | | | | | | | |
| Q | PM Țig | 6 | 6 | | Q | PM Țig | 2 | 7 | 5 | | | | | | | | | |
| WC | A Shimizu | 4 | 2 | | | | | | | 8 | L Siegemund | 3 | 6 | 2 | | | | |
| | C McHale | 6 | 6 | | | | | | | 2 | V Kudermetova | 6 | 4 | 6 | | | | |
| | G Minnen | 2 | 4 | | | C McHale | 6$^7$ | 2 | | | | | | | | | | |
| | V Lepchenko | 4 | 2 | | 2 | V Kudermetova | 7$^9$ | 6 | | | | | | | | | | |
| 2 | V Kudermetova | 6 | 6 | | | | | | | | | | | | | | | |

## Qualifying
### Seeds

* Patricia Maria Țig (qualified)
* Han Na-lae (qualifying competition)
* Zoe Hives (qualified)
* Viktoriya Tomova (qualified)
* Valeria Savinykh (qualified)
* Destanee Aiava (first round)
* Mayo Hibi (qualifying competition)
* Georgina García Pérez (first round)
* Leylah Annie Fernandez (qualified)
* Yuki Naito (first round)
* Jang Su-jeong (qualifying competition)
* Miharu Imanishi (qualifying competition)

### Qualifiers

* Patricia Maria Țig
* Leylah Annie Fernandez
* Zoe Hives
* Viktoriya Tomova
* Valeria Savinykh
* Junri Namigata

### Draw
#### First qualifier

| First round | First round | First round | First round | First round | Qualifying competition | Qualifying competition | Qualifying competition | Qualifying competition |
| 1 | Patricia Maria Țig | 3 | 7 | 6 | | | | |
| | Chihiro Muramatsu | 6 | 5 | 3 | | | | |
| | Chihiro Muramatsu | 6 | 5 | 3 | 1 | Patricia Maria Țig | 6 | 6 |
| | | | | | | Kyōka Okamura | 1 | 1 |
| | Kyōka Okamura | 6 | 6 | | | Kyōka Okamura | 1 | 1 |
| 10 | Yuki Naito | 2 | 4 | | | | | |

#### Second qualifier

| First round | First round | First round | First round | Qualifying competition | Qualifying competition | Qualifying competition | Qualifying competition |
| 2 | Han Na-lae | 7$^7$ | 3 | | | | |
| WC | Miyu Kato | 6$^1$ | 2$^r$ | | | | |
| WC | Miyu Kato | 6$^1$ | 2$^r$ | 2 | Han Na-lae | 3 | 2 |
| | | | | 9 | Leylah Annie Fernandez | 6 | 6 |
| | Erina Hayashi | 0 | 4 | 9 | Leylah Annie Fernandez | 6 | 6 |
| 9 | Leylah Annie Fernandez | 6 | 6 | | | | |

#### Third qualifier

| First round | First round | First round | First round | First round | Qualifying competition | Qualifying competition | Qualifying competition | Qualifying competition |
| 3 | Zoe Hives | 3 | 6 | 7$^7$ | | | | |
| | Akiko Omae | 6 | 2 | 6$^5$ | | | | |
| | Akiko Omae | 6 | 2 | 6$^5$ | 3 | Zoe Hives | 6 | 6 |
| | | | | | 12 | Miharu Imanishi | 3 | 4 |
| | Mai Hontama | 4 | 6 | 4 | 12 | Miharu Imanishi | 3 | 4 |
| 12 | Miharu Imanishi | 6 | 2 | 6 | | | | |

#### Fourth qualifier

| First round | First round | First round | First round | Qualifying competition | Qualifying competition | Qualifying competition | Qualifying competition | Qualifying competition |
| 4 | Viktoriya Tomova | 6 | 6 | | | | | |
| | Ena Shibahara | 4 | 1 | | | | | |
| | Ena Shibahara | 4 | 1 | 4 | Viktoriya Tomova | 4 | 6 | 6 |
| | | | | 7 | Mayo Hibi | 6 | 4 | 2 |
| WC | Himari Sato | 1 | 2 | 7 | Mayo Hibi | 6 | 4 | 2 |
| 7 | Mayo Hibi | 6 | 6 | | | | | |

#### Fifth qualifier

| First round | First round | First round | First round | Qualifying competition | Qualifying competition | Qualifying competition | Qualifying competition |
| 5 | Valeria Savinykh | 6 | 2 | | | | |
| WC | Ayumi Morita | 2 | 3$^r$ | | | | |
| WC | Ayumi Morita | 2 | 3$^r$ | 5 | Valeria Savinykh | 6 | 7 |
| | | | | 11 | Jang Su-jeong | 4 | 5 |
| PR | Susanne Celik | 4 | 4 | 11 | Jang Su-jeong | 4 | 5 |
| 11 | Jang Su-jeong | 6 | 6 | | | | |

#### Sixth qualifier

| First round | First round | First round | First round | First round | Qualifying competition | Qualifying competition | Qualifying competition | Qualifying competition | Qualifying competition |
| 6 | Destanee Aiava | 2 | 4 | | | | | | |
| | Junri Namigata | 6 | 6 | | | | | | |
| | Junri Namigata | 6 | 6 | | | Junri Namigata | 6 | 2 | 6 |
| | | | | | WC | Moyuka Uchijima | 2 | 6 | 4 |
| WC | Moyuka Uchijima | 2 | 6 | 6 | WC | Moyuka Uchijima | 2 | 6 | 4 |
| 8 | Georgina García Pérez | 6 | 3 | 0 | | | | | |