# 2022 Keio Challenger – Men's singles

Kwon Soon-woo was the defending champion but chose not to defend his title.
Christopher O'Connell won the title after defeating Yosuke Watanuki 6–1, 6–7$^{(5–7)}$, 6–3 in the final.

## Seeds

* Christopher O'Connell (champion)
* John Millman (quarterfinals, withdrew)
* Kaichi Uchida (quarterfinals)
* Damir Džumhur (quarterfinals)
* Wu Tung-lin (quarterfinals)
* Hiroki Moriya (first round)
* Yosuke Watanuki (final)
* Zdeněk Kolář (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 | Final |
| 1 | Christopher O'Connell | 6 | 6 | | | | | |
| | Sho Shimabukuro | 3 | 3 | | | | | |
| | Sho Shimabukuro | 3 | 3 | 1 | Christopher O'Connell | 6 | 6$^5$ | 6 |
| | | | | 7 | Yosuke Watanuki | 1 | 7$^7$ | 3 |
| 7 | Yosuke Watanuki | 7 | 7$^7$ | 7 | Yosuke Watanuki | 1 | 7$^7$ | 3 |
| | Nino Serdarušić | 5 | 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 | Quarterfinals | Semifinals | Semifinals | Semifinals | Semifinals |
| 1 | C O'Connell | 6 | 7$^7$ | | | | | | | | | | | | | | | |
| | R Ramanathan | 4 | 6$^3$ | | 1 | C O'Connell | 6 | 6 | | | | | | | | | | |
| WC | S Hazawa | 4 | 2 | | | E Kırkın | 3 | 4 | | | | | | | | | | |
| | E Kırkın | 6 | 6 | | | | | | | 1 | C O'Connell | 6$^5$ | 7$^7$ | 6 | | | | |
| WC | Tomoya Fujiwara | 7$^8$ | 1 | 4 | | | | | | 5 | T-l Wu | 7$^7$ | 6$^4$ | 4 | | | | |
| LL | Rimpei Kawakami | 6$^6$ | 6 | 6 | LL | R Kawakami | 2 | 4 | | | | | | | | | | |
| PR | Y Sugita | 3 | 3 | | 5 | T-l Wu | 6 | 6 | | | | | | | | | | |
| 5 | T-l Wu | 6 | 6 | | | | | | | | | | | | 1 | C O'Connell | 6 | 6 |
| 4 | D Džumhur | 6 | 6 | | | | | | | | | | | | | S Shimabukuro | 3 | 3 |
| Q | Ryota Tanuma | 3 | 1 | | 4 | D Džumhur | 5 | 6 | 6 | | | | | | | | | |
| Q | J Trotter | 6 | 6 | | Q | J Trotter | 7 | 4 | 4 | | | | | | | | | |
| Q | J Mridha | 4 | 1 | | | | | | | 4 | D Džumhur | 4 | 1 | | | | | |
| | S Shimabukuro | 6 | 6 | | | | | | | | S Shimabukuro | 6 | 6 | | | | | |
| Q | Yuki Mochizuki | 2 | 4 | | | S Shimabukuro | 6 | 6 | | | | | | | | | | |
| | J Jung | 6 | 6 | | | J Jung | 4 | 3 | | | | | | | | | | |
| 8 | Z Kolář | 2 | 1 | | | | | | | | | | | | | | | |

### 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 | Yo Watanuki | 6 | 6 | | | | | | | | | | | | | | | |
| | N Nakagawa | 4 | 4 | | 7 | Yo Watanuki | 5 | 6 | 2 | | | | | | | | | |
| | NH Lý | 6 | 4 | 0 | PR | T Ito | 7 | 0 | 1$^r$ | | | | | | | | | |
| PR | T Ito | 4 | 6 | 6 | | | | | | 7 | Yo Watanuki | 7 | 4 | 6 | | | | |
| WC | M Imamura | 3 | 4 | | | | | | | 3 | K Uchida | 5 | 6 | 3 | | | | |
| | Y-s Chung | 6 | 6 | | | Y-s Chung | 6$^4$ | 3 | | | | | | | | | | |
| Q | S-c Hong | 6 | 5 | 3 | 3 | K Uchida | 7$^7$ | 6 | | | | | | | | | | |
| 3 | K Uchida | 3 | 7 | 6 | | | | | | | | | | | 7 | Yo Watanuki | 7 | 7$^7$ |
| 6 | H Moriya | 6$^7$ | 6 | 4 | | | | | | | | | | | | N Serdarušić | 5 | 6$^5$ |
| | FC Jianu | 7$^9$ | 0 | 6 | | FC Jianu | 4 | 6 | 5 | | | | | | | | | |
| | S Mochizuki | 3 | 7$^7$ | 1 | | N Serdarušić | 6 | 4 | 7 | | | | | | | | | |
| | N Serdarušić | 6 | 6$^5$ | 6 | | | | | | | N Serdarušić | w/o | | | | | | |
| | ND Ionel | 5 | 2 | | | | | | | 2 | J Millman | | | | | | | |
| | F Ferreira Silva | 7 | 6 | | | F Ferreira Silva | 3 | 2 | | | | | | | | | | |
| Q | T Ichikawa | 3 | 6$^5$ | | 2 | J Millman | 6 | 6 | | | | | | | | | | |
| 2 | J Millman | 6 | 7$^7$ | | | | | | | | | | | | | | | |