# 2018 Knoxville Challenger – Singles

Filip Peliwo was the defending champion but chose not to defend his title.
Reilly Opelka won the title after defeating Bjorn Fratangelo 7–5, 4–6, 7–6$^{(7–2)}$ in the final.

## Seeds

* Tennys Sandgren (second round)
* Marcel Granollers (first round)
* Bradley Klahn (second round)
* Michael Mmoh (quarterfinals, withdrew)
* Tim Smyczek (quarterfinals)
* Jason Jung (second round)
* Peter Polansky (second round)
* Reilly Opelka (champion)

## 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 |
| | Nikola Milojević | 3 | 4 | | | | | |
| 8 | Reilly Opelka | 6 | 6 | | | | | |
| 8 | Reilly Opelka | 6 | 6 | 8 | Reilly Opelka | 7 | 4 | 7$^7$ |
| | | | | | Bjorn Fratangelo | 5 | 6 | 6$^2$ |
| | Christopher Eubanks | 6$^4$ | 4 | | Bjorn Fratangelo | 5 | 6 | 6$^2$ |
| | Bjorn Fratangelo | 7$^7$ | 6 | | | | | |

### Top half

| First round | First round | First round | First round | Second round | Second round | Second round | Second round | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Semifinals | Semifinals | Semifinals | Semifinals |
| 1/WC | T Sandgren | 6 | 6 | | | | | | | | | | | | |
| | H Laaksonen | 3 | 0 | 1/WC | T Sandgren | 4 | 4 | | | | | | | | |
| | R Quiroz | 6$^4$ | 4 | | B Rola | 6 | 6 | | | | | | | | |
| | B Rola | 7$^7$ | 6 | | | | | | B Rola | 4 | 2 | | | | |
| | N Serdarušić | 2 | 4 | | | | | | N Milojević | 6 | 6 | | | | |
| | N Milojević | 6 | 6 | | N Milojević | 6 | 6 | | | | | | | | |
| WC | Timo Stodder | 1 | 3 | 6 | J Jung | 0 | 4 | | | | | | | | |
| 6 | J Jung | 6 | 6 | | | | | | | | | | N Milojević | 3 | 4 |
| 4 | M Mmoh | 6 | 6 | | | | | | | | | 8 | R Opelka | 6 | 6 |
| Q | Evan Song | 2 | 3 | 4 | M Mmoh | 6 | 6 | | | | | | | | |
| Q | M Ymer | 6 | 6 | Q | M Ymer | 3 | 2 | | | | | | | | |
| | K Majchrzak | 4 | 4 | | | | | 4 | M Mmoh | | | | | | |
| Q | Mi Redlicki | 7$^7$ | 6 | | | | | 8 | R Opelka | w/o | | | | | |
| | M Arévalo | 6$^5$ | 4 | Q | Mi Redlicki | 6$^{10}$ | 6$^6$ | | | | | | | | |
| Q | E Gómez | 2 | 3 | 8 | R Opelka | 7$^{12}$ | 7$^8$ | | | | | | | | |
| 8 | R Opelka | 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 |
| 7 | P Polansky | 6 | 6 | | | | | | | | | | | | | |
| Alt | C Harrison | 2 | 2 | | 7 | P Polansky | 3 | 4 | | | | | | | | |
| | C Eubanks | 7 | 6$^3$ | 6 | | C Eubanks | 6 | 6 | | | | | | | | |
| WC | J. J. Wolf | 5 | 7$^7$ | 4 | | | | | | | C Eubanks | 4 | | | | |
| WC | Preston Touliatos | 3 | 2 | | | | | | | | E Karlovskiy | 1$^r$ | | | | |
| | E Karlovskiy | 6 | 6 | | | E Karlovskiy | 5 | 6 | 6 | | | | | | | |
| | JC Aragone | 2 | 6$^7$ | | 3 | B Klahn | 7 | 4 | 4 | | | | | | | |
| 3 | B Klahn | 6 | 7$^9$ | | | | | | | | | | | C Eubanks | 6$^4$ | 4 |
| 5 | T Smyczek | 3 | 6 | 6 | | | | | | | | | | B Fratangelo | 7$^7$ | 6 |
| | J-P Smith | 6 | 3 | 2 | 5 | T Smyczek | 6 | 7$^7$ | | | | | | | | |
| | D Köpfer | 6 | 2 | 6 | | D Köpfer | 4 | 6$^4$ | | | | | | | | |
| Alt | M Krueger | 1 | 6 | 2 | | | | | | 5 | T Smyczek | 2 | 1 | | | |
| SE | T Paul | 4 | 4 | | | | | | | | B Fratangelo | 6 | 6 | | | |
| | B Fratangelo | 6 | 6 | | | B Fratangelo | 7$^7$ | 6$^4$ | 6 | | | | | | | |
| | T Kamke | 6 | 3 | 6 | | T Kamke | 6$^4$ | 7$^7$ | 4 | | | | | | | |
| 2 | M Granollers | 4 | 6 | 4 | | | | | | | | | | | | |