# 2018 International Challenger Zhangjiagang – Singles

Jason Jung was the defending champion but lost in the final to Yasutaka Uchiyama.
Uchiyama won the title after defeating Jung 6–2, 6–2 in the final.

## Seeds

* Jason Jung (final)
* Tatsuma Ito (second round)
* Zhang Ze (first round)
* Go Soeda (second round)
* Filip Peliwo (first round)
* Miomir Kecmanović (semifinals)
* Hiroki Moriya (second round)
* Alexander Bublik (semifinals)

## 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 |
| 1 | Jason Jung | 7$^7$ | 6$^5$ | 6 | | | | |
| 8 | Alexander Bublik | 6$^3$ | 7$^7$ | 0 | | | | |
| 8 | Alexander Bublik | 6$^3$ | 7$^7$ | 0 | 1 | Jason Jung | 2 | 2 |
| | | | | | | Yasutaka Uchiyama | 6 | 6 |
| | Yasutaka Uchiyama | 6 | 4 | 7 | | Yasutaka Uchiyama | 6 | 6 |
| 6 | Miomir Kecmanović | 3 | 6 | 5 | | | | |

### 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 | Semifinals |
| 1 | J Jung | 6 | 6 | | | | | | | | | | | | | | | |
| Q | Y Shimizu | 4 | 3 | | 1 | J Jung | 6 | 6 | | | | | | | | | | |
| | Z Li | 0 | 6 | 3 | WC | Zh Zhang | 4 | 4 | | | | | | | | | | |
| WC | Zh Zhang | 6 | 1 | 6 | | | | | | 1 | J Jung | 7 | 6 | | | | | |
| | T-h Yang | 4 | 1$^r$ | | | | | | | | A Santillan | 5 | 2 | | | | | |
| | A Santillan | 6 | 3 | | | A Santillan | 7 | 6$^4$ | 6 | | | | | | | | | |
| WC | R Te | 6 | 6 | | WC | R Te | 5 | 7$^7$ | 4 | | | | | | | | | |
| 5 | F Peliwo | 4 | 4 | | | | | | | | | | | 1 | J Jung | 7$^7$ | 6$^5$ | 6 |
| 4 | G Soeda | 7 | 7 | | | | | | | | | | | 8 | A Bublik | 6$^3$ | 7$^7$ | 0 |
| | A Bega | 5 | 5 | | 4 | G Soeda | 5 | 6 | 2 | | | | | | | | | |
| | Y-s Chung | 3 | 6 | 6 | | Y-s Chung | 7 | 3 | 6 | | | | | | | | | |
| | R Safiullin | 6 | 4 | 3 | | | | | | | Y-s Chung | 4 | 4 | | | | | |
| Q | D Kelly | 7$^7$ | 7 | | | | | | | 8 | A Bublik | 6 | 6 | | | | | |
| | S-w Kwon | 6$^5$ | 5 | | Q | D Kelly | 5 | 4 | | | | | | | | | | |
| LL | Y Takahashi | 3 | 4 | | 8 | A Bublik | 7 | 6 | | | | | | | | | | |
| 8 | A Bublik | 6 | 6 | | | | | | | | | | | | | | | |

### 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 | Semifinals | Semifinals | Semifinals | Semifinals | Semifinals |
| 7 | H Moriya | 7$^8$ | 6 | | | | | | | | | | | | | | | |
| Q | T Lamasine | 6$^6$ | 2 | | 7 | H Moriya | 6 | 6$^5$ | 3 | | | | | | | | | |
| | Y Uchiyama | 6 | 4 | | | Y Uchiyama | 4 | 7$^7$ | 6 | | | | | | | | | |
| | B Kavčič | 3 | 2$^r$ | | | | | | | | Y Uchiyama | 6 | 6 | | | | | |
| | U Ignatik | 6 | 7$^7$ | | | | | | | | U Ignatik | 4 | 3 | | | | | |
| | A Šetkić | 2 | 6$^3$ | | | U Ignatik | 7$^8$ | 6 | | | | | | | | | | |
| | D-h Lee | 6 | 5 | 6 | | D-h Lee | 6$^6$ | 1 | | | | | | | | | | |
| 3 | Ze Zhang | 3 | 7 | 0 | | | | | | | | | | | Y Uchiyama | 6 | 4 | 7 |
| 6 | M Kecmanović | 6 | 3 | 6 | | | | | | | | | | 6 | M Kecmanović | 3 | 6 | 5 |
| | M Purcell | 3 | 6 | 3 | 6 | M Kecmanović | 2 | 6 | 6 | | | | | | | | | |
| Q | F Ferreira Silva | 4 | 4 | | | J Rodionov | 6 | 3 | 3 | | | | | | | | | |
| | J Rodionov | 6 | 6 | | | | | | | 6 | M Kecmanović | 6 | 6 | | | | | |
| WC | Y Wu | 6 | 6 | | | | | | | WC | Y Wu | 4 | 4 | | | | | |
| WC | Y He | 3 | 4 | | WC | Y Wu | 7$^8$ | 4 | 6 | | | | | | | | | |
| | S Diez | 4 | 1 | | 2 | T Ito | 6$^6$ | 6 | 3 | | | | | | | | | |
| 2 | T Ito | 6 | 6 | | | | | | | | | | | | | | | |