| Singles | |
|---|---|
| 2018 Las Vegas Challenger | |
| Champion |  Thanasi Kokkinakis |
| Runner-up |  Blaž Rola |
| Score | 6–4, 6–4 |
Stefan Kozlov was the defending champion but lost in the first round to Kamil Majchrzak.
Thanasi Kokkinakis won the title after defeating Blaž Rola 6–4, 6–4 in the final. [1]
Lloyd Harris (second round)
Adrián Menéndez Maceiras (second round)
Casper Ruud (semifinals)
Jason Jung (quarterfinals)
Noah Rubin (first round) Reilly Opelka (withdrew)
Dominik Köpfer (first round)
Marcelo Arévalo (second round)| Semifinals | Final | ||||||||||||
| Thanasi Kokkinakis | 6 | 6 | |||||||||||
| 3 | Casper Ruud | 4 | 1 | ||||||||||
| Thanasi Kokkinakis | 6 | 6 | |||||||||||
| Blaž Rola | 4 | 4 | |||||||||||
| John-Patrick Smith | 3 | 5 | |||||||||||
| Blaž Rola | 6 | 7 | |||||||||||
| First round | Second round | Quarterfinals | Semifinals | ||||||||||||||||||||||||
| 1 | L Harris | 6 | 6 | ||||||||||||||||||||||||
 J Ward | 4 | 4 | 1 | L Harris | 4 | 3 | |||||||||||||||||||||
| T Kokkinakis | 77 | 6 | T Kokkinakis | 6 | 6 | ||||||||||||||||||||||
| WC |  A Cozbinov | 65 | 1 | T Kokkinakis | 6 | 6 | |||||||||||||||||||||
| Q | T Paul | 6 | 77 |  D King | 1 | 4 | |||||||||||||||||||||
| K King | 1 | 62 | Q | T Paul | 4 | 4 | |||||||||||||||||||||
| D King | 6 | 6 | D King | 6 | 6 | ||||||||||||||||||||||
| 7 | D Köpfer | 4 | 4 | T Kokkinakis | 6 | 6 | |||||||||||||||||||||
| 3 | C Ruud | 6 | 3 | 6 | 3 | C Ruud | 4 | 1 | |||||||||||||||||||
| M Krueger | 3 | 6 | 3 | 3 | C Ruud | 6 | 6 | ||||||||||||||||||||
| LL | E King | 6 | 6 | LL | E King | 3 | 2 | ||||||||||||||||||||
| T Robredo | 3 | 4 | 3 | C Ruud | 7 | 7 | |||||||||||||||||||||
 K Majchrzak | 6 | 6 | K Majchrzak | 5 | 5 | ||||||||||||||||||||||
| S Kozlov | 0 | 2 | K Majchrzak | 2 | 6 | 6 | |||||||||||||||||||||
| JC Aragone | 2 | 6 | 63 | 8 | M Arévalo | 6 | 1 | 4 | |||||||||||||||||||
| 8 | M Arévalo | 6 | 4 | 77 | |||||||||||||||||||||||
| First round | Second round | Quarterfinals | Semifinals | ||||||||||||||||||||||||
| LL |  J Sels | 77 | 5 | 4 | |||||||||||||||||||||||
| J-P Smith | 64 | 7 | 6 | J-P Smith | 6 | 6 | |||||||||||||||||||||
| WC |  M Torpegaard | 4 | 6 | 66 |  C İlkel | 3 | 1 | ||||||||||||||||||||
| C İlkel | 6 | 3 | 78 | J-P Smith | 77 | 6 | |||||||||||||||||||||
| Alt | J Choinski | 3 | 4 | 4 | J Jung | 63 | 3 | ||||||||||||||||||||
| Q | R Ortega Olmedo | 6 | 6 | Q | R Ortega Olmedo | 4 | 4 | ||||||||||||||||||||
| LL | A Sarkissian | 65 | 4 | 4 | J Jung | 6 | 6 | ||||||||||||||||||||
| 4 | J Jung | 77 | 6 | J-P Smith | 3 | 5 | |||||||||||||||||||||
| 5 | N Rubin | 3 | 6 | 3 | B Rola | 6 | 7 | ||||||||||||||||||||
| B Rola | 6 | 1 | 6 | B Rola | 6 | 6 | |||||||||||||||||||||
| Q | T-S Kwiatkowski | 6 | 6 | Q | T-S Kwiatkowski | 3 | 4 | ||||||||||||||||||||
| WC | Evan Song | 4 | 4 | B Rola | 6 | 77 | |||||||||||||||||||||
 N Serdarušić | 64 | 4 | Q |  M Bourgue | 4 | 61 | |||||||||||||||||||||
| Q | M Bourgue | 77 | 6 | Q | M Bourgue | 6 | 0 | 6 | |||||||||||||||||||
| WC | J. J. Wolf | 3 | 3 | 2 | A Menéndez Maceiras | 4 | 6 | 3 | |||||||||||||||||||
| 2 | A Menéndez Maceiras | 6 | 6 | ||||||||||||||||||||||||
Uladzimir Ignatik was the defending champion, but decided not to compete.
Rubén Ramírez Hidalgo was the defending champion, but decided not to compete.
Last year's champion Paul Capdeville was not defending his title.
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Nikoloz Basilashvili won the title, defeating Lukáš Lacko in the final, 4–6, 6–4, 6–3.
Máximo González was the defending champion, but he lost in the second round.
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Sam Querrey was the defending champion, but chose to compete in the Japan Open instead of defending his title.
Henri Laaksonen won the title, defeating Taylor Fritz in the final 4–6, 6–2, 6–2
Rafael Nadal was the defending champion, but lost to Dominic Thiem in the semifinals.
Pablo Cuevas was the defending champion and successfully defended his title, defeating Pablo Carreño Busta in the final, 7–6(7–4), 6–3.
Go Soeda was the defending champion but chose not to defend his title.
Blaž Rola was the defending champion but lost in the first round to Marc Polmans.
Thanasi Kokkinakis was the defending champion but chose not to defend his title.
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Francisco Cerúndolo was the defending champion but chose not to defend his title.
Blaž Rola was the defending champion but chose not to defend his title.