# 2019 Yokkaichi Challenger – Singles

This was the first edition of the tournament.
Yūichi Sugita won the title after defeating James Duckworth 3–6, 6–3, 7–6$^{(7–1)}$ in the final.

## Seeds

All seeds receive a bye into the second round.
* Yasutaka Uchiyama (second round)
* James Duckworth (final)
* Tatsuma Ito (semifinals)
* Chung Hyeon (quarterfinals, withdrew)
* Yūichi Sugita (champion)
* Zhang Ze (second round)
* Hiroki Moriya (third round)
* Chung Yun-seong (third round)
* Saketh Myneni (quarterfinals)
* Wu Tung-lin (quarterfinals)
* Nam Ji-sung (quarterfinals)
* Yang Tsung-hua (third round)
* Makoto Ochi (second round)
* Yusuke Takahashi (third round)
* Renta Tokuda (second round)
* Lý Hoàng Nam (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

| Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Semifinals | Semifinals | Semifinals | Semifinals | Final | Final | Final | Final | Final |
| ITF | Sho Shimabukuro | 6$^1$ | 6 | 6 | | | | | | | | | |
| 11 | Nam Ji-sung | 7$^7$ | 3 | 2 | | | | | | | | | |
| 11 | Nam Ji-sung | 7$^7$ | 3 | 2 | ITF | Sho Shimabukuro | 5 | 3 | | | | | |
| | | | | | 5 | Yūichi Sugita | 7 | 6 | | | | | |
| 4 | Chung Hyeon | | | | 5 | Yūichi Sugita | 7 | 6 | | | | | |
| 5 | Yūichi Sugita | w/o | | | | | | | | | | | |
| 5 | Yūichi Sugita | w/o | | | | | | | 5 | Yūichi Sugita | 3 | 6 | 7$^7$ |
| | | | | | | | | | 2 | James Duckworth | 6 | 3 | 6$^1$ |
| 9 | Saketh Myneni | 6$^5$ | 1 | | | | | | | | | | | 2 | James Duckworth | 6 | 3 | 6$^1$ |
| 3 | Tatsuma Ito | 7$^7$ | 6 | | | | | | | | | | |
| 3 | Tatsuma Ito | 7$^7$ | 6 | | 3 | Tatsuma Ito | 3 | 4 | | | | | |
| | | | | | 2 | James Duckworth | 6 | 6 | | | | | |
| 10 | Wu Tung-lin | 3 | 1 | | 2 | James Duckworth | 6 | 6 | | | | | |
| 2 | James Duckworth | 6 | 6 | | | | | | | | | | |

### Top half
#### Section 1

| First round | First round | First round | First round | Second round | Second round | Second round | Second round | Second round | Third round | Third round | Third round | Third round | Third round | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals |
| | | | | 1 | Y Uchiyama | 6$^7$ | 7$^7$ | 3 | | | | | | | | | | |
| ITF | S Shimabukuro | 6 | 6 | ITF | S Shimabukuro | 7$^9$ | 6$^4$ | 6 | | | | | | | | | | |
| ITF | Yuki Mochizuki | 4 | 2 | | | | | | ITF | S Shimabukuro | 6 | 1 | | | | | | |
| | T Matsui | 6 | 7$^{15}$ | | | | | | | T Matsui | 4 | 0$^r$ | | | | | | |
| Alt | JP Fruttero | 3 | 6$^{13}$ | | T Matsui | 7$^7$ | 7$^7$ | | | | | | | | | | | |
| | | | | 13 | Makoto Ochi | 6$^5$ | 6$^4$ | | | | | | | | | | | |
| | | | | | | | | | | | | | | ITF | S Shimabukuro | 6$^1$ | 6 | 6 |
| | | | | | | | | | | | | | | 11 | J-s Nam | 7$^7$ | 3 | 2 |
| | | | | 11 | J-s Nam | 6 | 6 | | | | | | | | | | | |
| ITF | Jumpei Yamasaki | 6 | 6 | ITF | J Yamasaki | 3 | 2 | | | | | | | | | | | |
| | B Ellis | 4 | 4 | | | | | | 11 | J-s Nam | 6 | 5 | 7$^7$ | | | | | |
| | E Zhu | 6$^4$ | 5 | | | | | | 7 | H Moriya | 2 | 7 | 6$^1$ | | | | | |
| | W Trongcharoenchaikul | 7$^7$ | 4$^r$ | | E Zhu | 6$^5$ | 6$^5$ | | | | | | | | | | | |
| | | | | 7 | H Moriya | 7$^7$ | 7$^7$ | | | | | | | | | | | |

#### Section 2

| First round | First round | First round | First round | First round | Second round | Second round | Second round | Second round | Second round | Third round | Third round | Third round | Third round | Third round | Quarterfinals | Quarterfinals | Quarterfinals |
| | | | | | 4 | Hy Chung | 6 | 6 | | | | | | | | | |
| | M Romios | 6$^4$ | 6 | 6 | | M Romios | 3 | 1 | | | | | | | | | |
| ITF | B Lock | 7$^7$ | 2 | 2 | | | | | | 4 | Hy Chung | 3 | 6 | 6 | | | |
| Alt | CJ Lock | 2 | 2 | | | | | | | 14 | Y Takahashi | 6 | 1 | 4 | | | |
| | Kazuki Nishiwaki | 6 | 6 | | | K Nishiwaki | 5 | 6 | 3 | | | | | | | | |
| | | | | | 14 | Y Takahashi | 7 | 3 | 6 | | | | | | | | |
| | | | | | | | | | | | | | | | 4 | Hy Chung | |
| | | | | | | | | | | | | | | | 5 | Y Sugita | w/o |
| | | | | | 12 | T-h Yang | 1 | 6 | 6 | | | | | | | | |
| | Y Shimizu | 6 | 6 | | | Y Shimizu | 6 | 1 | 4 | | | | | | | | |
| | M-k Song | 3 | 3 | | | | | | | 12 | T-h Yang | 3 | 1 | | | | |
| WC | Yuya Ito | 6 | 6 | | | | | | | 5 | Y Sugita | 6 | 6 | | | | |
| | H Bourchier | 3 | 3 | | WC | Y Ito | 3 | 6 | 2 | | | | | | | | |
| | | | | | 5 | Y Sugita | 6 | 3 | 6 | | | | | | | | |

### Bottom half
#### Section 3

| First round | First round | First round | First round | First round | Second round | Second round | Second round | Second round | Second round | Third round | Third round | Third round | Third round | Third round | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals |
| | | | | | 8 | Y-s Chung | 7$^7$ | 6 | | | | | | | | | | |
| | D Kelly | 6$^2$ | 0$^r$ | | | A Ayeni | 6$^1$ | 3 | | | | | | | | | | |
| | Alafia Ayeni | 7$^7$ | 0 | | | | | | | 8 | Y-s Chung | 3 | 6 | 3 | | | | |
| | Kazuma Kawachi | 6 | 4 | 0$^r$ | | | | | | 9 | S Myneni | 6 | 3 | 6 | | | | |
| WC | Yasunori Hashikawa | 2 | 6 | 4 | WC | Y Hashikawa | 2 | 6$^4$ | | | | | | | | | | |
| | | | | | 9 | S Myneni | 6 | 7$^7$ | | | | | | | | | | |
| | | | | | | | | | | | | | | | 9 | S Myneni | 6$^5$ | 1 |
| | | | | | | | | | | | | | | | 3 | T Ito | 7$^7$ | 6 |
| | | | | | 15 | Renta Tokuda | 6 | 6$^7$ | 0 | | | | | | | | | |
| WC | S Hazawa | 6 | 6 | | WC | S Hazawa | 4 | 7$^9$ | 6 | | | | | | | | | |
| | T Fancutt | 4 | 1 | | | | | | | WC | S Hazawa | 0 | 3 | | | | | |
| | Sora Fukuda | 4 | 3 | | | | | | | 3 | T Ito | 6 | 6 | | | | | |
| ITF | K Takeuchi | 6 | 6 | | ITF | K Takeuchi | 6$^5$ | 1 | | | | | | | | | | |
| | | | | | 3 | T Ito | 7$^7$ | 6 | | | | | | | | | | |

#### Section 4

| First round | First round | First round | Second round | Second round | Second round | Second round | Second round | Third round | Third round | Third round | Third round | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals |
| | | | 6 | Ze Zhang | 6 | 6$^5$ | 5 | | | | | | | | |
| Kosuke Ogura | 1 | 3 | | S Sekiguchi | 3 | 7$^7$ | 7 | | | | | | | | |
| Shuichi Sekiguchi | 6 | 6 | | | | | | | S Sekiguchi | 4 | 0$^r$ | | | | |
| Issei Okamura | 3 | 3 | | | | | | 10 | T-l Wu | 6 | 0 | | | | |
| J Cui | 6 | 6 | | J Cui | 3 | 6$^1$ | | | | | | | | | |
| | | | 10 | T-l Wu | 6 | 7$^7$ | | | | | | | | | |
| | | | | | | | | | | | | 10 | T-l Wu | 3 | 1 |
| | | | | | | | | | | | | 2 | J Duckworth | 6 | 6 |
| | | | 16 | NH Lý | 6 | 2 | 3 | | | | | | | | |
| Shintaro Imai | 6 | 6 | | S Imai | 2 | 6 | 6 | | | | | | | | |
| N Tajima | 2 | 3 | | | | | | | S Imai | 2 | 3 | | | | |
| Ren Nakamura | 1 | 2 | | | | | | 2 | J Duckworth | 6 | 6 | | | | |
| L Catarina | 6 | 6 | | L Catarina | 1 | 3 | | | | | | | | | |
| | | | 2 | J Duckworth | 6 | 6 | | | | | | | | | |