# 2023 Champaign–Urbana Challenger – Singles

Ben Shelton was the defending champion but chose not to defend his title.
Patrick Kypson won the title after defeating Alex Michelsen 6–4, 6–3 in the final.

## Seeds

* Aleksandar Kovacevic (quarterfinals)
* Alex Michelsen (final)
* Emilio Nava (first round)
* Titouan Droguet (semifinals)
* Denis Kudla (first round, retired)
* Beibit Zhukayev (second round)
* Patrick Kypson (champion)
* Martin Damm (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 | Final |
| 7 | Patrick Kypson | 6 | 6 | | | | | |
| WC | Ethan Quinn | 4 | 2 | | | | | |
| WC | Ethan Quinn | 4 | 2 | | 7 | Patrick Kypson | 6 | 6 |
| | | | | | 2 | Alex Michelsen | 4 | 3 |
| 4 | Titouan Droguet | 6 | 4 | 3 | 2 | Alex Michelsen | 4 | 3 |
| 2 | Alex Michelsen | 2 | 6 | 6 | | | | |

### Top 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 |
| 1 | A Kovacevic | 6 | 2 | 6 | | | | | | | | | | | | | |
| Q | C Williams | 3 | 6 | 4 | 1 | A Kovacevic | 7$^7$ | 6 | | | | | | | | | |
| Alt | S Kozlov | 6 | 3 | 4 | WC | K Ozoliņš | 6$^5$ | 3 | | | | | | | | | |
| WC | K Ozoliņš | 2 | 6 | 6 | | | | | 1 | A Kovacevic | 6$^2$ | 6 | 3 | | | | |
| Q | Hunter Heck | 3 | 4 | | | | | | 7 | P Kypson | 7$^7$ | 4 | 6 | | | | |
| WC | Kenta Miyoshi | 6 | 6 | | WC | K Miyoshi | 3 | 1 | | | | | | | | | |
| Q | M Whitehouse | 1 | 6$^5$ | | 7 | P Kypson | 6 | 6 | | | | | | | | | |
| 7 | P Kypson | 6 | 7$^7$ | | | | | | | | | | | 7 | P Kypson | 6 | 6 |
| 3 | Em Nava | 3 | 2 | | | | | | | | | | | WC | E Quinn | 4 | 2 |
| WC | E Quinn | 6 | 6 | | WC | E Quinn | 6 | 6 | | | | | | | | | |
| Alt | E Karlovskiy | 5 | 4$^r$ | | | S Kirchheimer | 1 | 4 | | | | | | | | | |
| | S Kirchheimer | 7 | 5 | | | | | | WC | E Quinn | 6 | 6 | | | | | |
| | N Serdarušić | 6 | 1 | 6 | | | | | | N Serdarušić | 3 | 3 | | | | | |
| | A Mayo | 3 | 6 | 3 | | N Serdarušić | 7$^7$ | 6 | | | | | | | | | |
| | E Dalla Valle | 1 | 1 | | 6 | B Zhukayev | 6$^5$ | 4 | | | | | | | | | |
| 6 | B Zhukayev | 6 | 6 | | | | | | | | | | | | | | |

### 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 | Semifinals |
| 5 | D Kudla | 7$^7$ | 5 | 0$^r$ | | | | | | | | | | | | | | |
| | M Krueger | 6$^4$ | 7 | 0 | | M Krueger | 7$^7$ | 6 | | | | | | | | | | |
| | C Rodesch | 7 | 4 | 4 | Q | A Rybakov | 6$^5$ | 1 | | | | | | | | | | |
| Q | A Rybakov | 5 | 6 | 6 | | | | | | M Krueger | 4 | 1 | | | | | | |
| | B Holt | 5 | 6 | 6 | | | | | 4 | T Droguet | 6 | 6 | | | | | | |
| Q | I Montes de la Torre | 7 | 0 | 1 | | B Holt | 4 | 3 | | | | | | | | | | |
| | V Durasovic | 2 | 3 | | 4 | T Droguet | 6 | 6 | | | | | | | | | | |
| 4 | T Droguet | 6 | 6 | | | | | | | | | | | 4 | T Droguet | 6 | 4 | 3 |
| 8 | M Damm | 7$^7$ | 6 | | | | | | | | | | | 2 | A Michelsen | 2 | 6 | 6 |
| Q | A Perez | 6$^3$ | 4 | | 8 | M Damm | 6 | 6 | | | | | | | | | | |
| | G Debru | 6$^7$ | 6 | 6$^4$ | Alt | M Rosenkranz | 3 | 4 | | | | | | | | | | |
| Alt | M Rosenkranz | 7$^9$ | 3 | 7$^7$ | | | | | 8 | M Damm | 1 | 6 | 4 | | | | | |
| | A McHugh | 2 | 6 | 3 | | | | | 2 | A Michelsen | 6 | 1 | 6 | | | | | |
| | S Fanselow | 6 | 4 | 6 | | S Fanselow | 3 | 2 | | | | | | | | | | |
| | B Tomic | 4 | 0 | | 2 | A Michelsen | 6 | 6 | | | | | | | | | | |
| 2 | A Michelsen | 6 | 6 | | | | | | | | | | | | | | | |