# 2023 Yokkaichi Challenger – Singles

Yosuke Watanuki was the defending champion but lost in the second round to Giovanni Fonio.
Zizou Bergs won the title after defeating Michael Mmoh 6–2, 7–6$^{(7–2)}$ in the final.

## Seeds

* Yosuke Watanuki (second round)
* Jurij Rodionov (first round)
* Michael Mmoh (final)
* Zizou Bergs (champion)
* Marc Polmans (semifinals)
* Zdeněk Kolář (second round)
* Leandro Riedi (first round)
* Hsu Yu-hsiou (first 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 |
| 5 | Marc Polmans | 5 | 4 | | | | |
| 4 | Zizou Bergs | 7 | 6 | | | | |
| 4 | Zizou Bergs | 7 | 6 | 4 | Zizou Bergs | 6 | 7$^7$ |
| | | | | 3 | Michael Mmoh | 2 | 6$^2$ |
| 3 | Michael Mmoh | 6 | 6 | 3 | Michael Mmoh | 2 | 6$^2$ |
| | Coleman Wong | 2 | 2 | | | | |

### 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 | Y Watanuki | 6 | 6 | | | | | | | | | | | | | | | |
| | Y Shimizu | 3 | 4 | | 1 | Y Watanuki | 6 | 2 | 5 | | | | | | | | | |
| | G Fonio | 4 | 7$^7$ | 7$^7$ | | G Fonio | 3 | 6 | 7 | | | | | | | | | |
| | K Ivanovski | 6 | 6$^5$ | 6$^5$ | | | | | | | G Fonio | 1 | 7$^8$ | 2 | | | | |
| | C İlkel | 4 | 5 | | | | | | | 5 | M Polmans | 6 | 6$^6$ | 6 | | | | |
| | M Echargui | 6 | 7 | | | M Echargui | 7 | 2 | 2 | | | | | | | | | |
| WC | R Noguchi | 3 | 4 | | 5 | M Polmans | 5 | 6 | 6 | | | | | | | | | |
| 5 | M Polmans | 6 | 6 | | | | | | | | | | | | 5 | M Polmans | 5 | 4 |
| 4 | Z Bergs | 5 | 6 | 6 | | | | | | | | | | | 4 | Z Bergs | 7 | 6 |
| | A Çelikbilek | 7 | 2 | 4 | 4 | Z Bergs | 6 | 6 | | | | | | | | | | |
| | K Uchida | 7$^8$ | 2 | 6 | | K Uchida | 4 | 3 | | | | | | | | | | |
| Q | J-s Nam | 6$^6$ | 6 | 1 | | | | | | 4 | Z Bergs | 6 | 7 | | | | | |
| | S-c Hong | 7$^9$ | 4 | 2 | | | | | | Q | J Trotter | 3 | 5 | | | | | |
| | O Jasika | 6$^7$ | 6 | 6 | | O Jasika | 6 | 2 | 4 | | | | | | | | | |
| Q | J Trotter | 7$^7$ | 6 | | Q | J Trotter | 2 | 6 | 6 | | | | | | | | | |
| 8 | Y-h Hsu | 6$^5$ | 2 | | | | | | | | | | | | | | | |

### Bottom half

| First round | First round | First round | First round | First round | Second round | Second round | Second round | Second round | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Semifinals | Semifinals | Semifinals | Semifinals |
| 7 | L Riedi | 2 | 2 | | | | | | | | | | | | | | |
| | L Tu | 6 | 6 | | | L Tu | 6 | 7$^8$ | | | | | | | | | |
| LL | Yuki Mochizuki | 0 | 4 | | | G Blancaneaux | 3 | 6$^6$ | | | | | | | | | |
| | G Blancaneaux | 6 | 6 | | | | | | | L Tu | 3 | 3 | | | | | |
| Q | H Moriya | 6 | 6 | | | | | | 3 | M Mmoh | 6 | 6 | | | | | |
| Q | T Ito | 3 | 2 | | Q | H Moriya | 6$^4$ | 0 | | | | | | | | | |
| WC | Renta Tokuda | 2 | 3 | | 3 | M Mmoh | 7$^7$ | 6 | | | | | | | | | |
| 3 | M Mmoh | 6 | 6 | | | | | | | | | | | 3 | M Mmoh | 6 | 6 |
| 6 | Z Kolář | 6 | 5 | 6 | | | | | | | | | | | C Wong | 2 | 2 |
| | Mathys Erhard | 1 | 7 | 2 | 6 | Z Kolář | 4 | 2 | | | | | | | | | |
| Q | Y Takahashi | 3 | 3 | | Q | A Holmgren | 6 | 6 | | | | | | | | | |
| Q | A Holmgren | 6 | 6 | | | | | | Q | A Holmgren | 6 | 5 | 4 | | | | |
| | N Nakagawa | 2 | 7$^7$ | 4 | | | | | | C Wong | 4 | 7 | 6 | | | | |
| | C Wong | 6 | 6$^5$ | 6 | | C Wong | 6 | 6 | | | | | | | | | |
| WC | R Sakamoto | 6 | 6 | | WC | R Sakamoto | 3 | 2 | | | | | | | | | |
| 2 | J Rodionov | 4 | 4 | | | | | | | | | | | | | | |