| Singles | |
|---|---|
| 2017 AON Open Challenger | |
| Champion |  Stefanos Tsitsipas |
| Runner-up |  Guillermo García López |
| Final score | 7–5, 7–6(7–2) |
Jerzy Janowicz was the defending champion but chose not to defend his title.
Stefanos Tsitsipas won the title after defeating Guillermo García López 7–5, 7–6(7–2) in the final.
Jan-Lennard Struff (quarterfinals)
Andreas Seppi (first round) Alessandro Giannessi (second round)
Laslo Đere (second round) Marco Cecchinato (first round)
Renzo Olivo (first round) Dustin Brown (second round)
Márton Fucsovics (semifinals, retired)| Semifinals | Final | ||||||||||||
| WC | Stefanos Tsitsipas | 6 | 1 | ||||||||||
| 8 | Márton Fucsovics | 0 | 0r | ||||||||||
| WC | Stefanos Tsitsipas | 7 | 77 | ||||||||||
| Guillermo García López | 5 | 62 | |||||||||||
| Guillermo García López | 6 | 65 | 6 | ||||||||||
| Stefano Napolitano | 2 | 77 | 3 | ||||||||||
| First round | Second round | Quarterfinals | Semifinals | ||||||||||||||||||||||||
| 1 | J-L Struff | 6 | 77 | ||||||||||||||||||||||||
| M Zekić | 4 | 62 | 1 | J-L Struff | 78 | 77 | |||||||||||||||||||||
| Alt |  H Hurkacz | 6 | 2 | 5 |  U Ignatik | 66 | 64 | ||||||||||||||||||||
| U Ignatik | 3 | 6 | 7 | 1 | J-L Struff | 2 | 3 | ||||||||||||||||||||
| G Andreozzi | 3 | 4 | WC | S Tsitsipas | 6 | 6 | |||||||||||||||||||||
| WC | S Tsitsipas | 6 | 6 | WC | S Tsitsipas | 6 | 6 | ||||||||||||||||||||
 A Šetkić | 1 | 77 | 6 | A Šetkić | 2 | 4 | |||||||||||||||||||||
| 5 | M Cecchinato | 6 | 65 | 3 | WC | S Tsitsipas | 6 | 1 | |||||||||||||||||||
| 4 | L Đere | 6 | 5 | 6 | 8 | M Fucsovics | 0 | 0r | |||||||||||||||||||
| Q | Gianluca Di Nicola | 1 | 7 | 4 | 4 | L Đere | 3 | 3 | |||||||||||||||||||
 E Ymer | 3 | 64 | A Balázs | 6 | 6 | ||||||||||||||||||||||
| A Balázs | 6 | 77 | A Balázs | 77 | 2 | 5 | |||||||||||||||||||||
| Q | T Pütz | 77 | 6 | 8 | M Fucsovics | 64 | 6 | 7 | |||||||||||||||||||
| Alt | F Gaio | 60 | 1 | Q | T Pütz | 1 | 2 | ||||||||||||||||||||
| S Caruso | 1 | 1 | 8 | M Fucsovics | 6 | 6 | |||||||||||||||||||||
| 8 | M Fucsovics | 6 | 6 | ||||||||||||||||||||||||
| First round | Second round | Quarterfinals | Semifinals | ||||||||||||||||||||||||
| 6 | R Olivo | 5 | 2 | ||||||||||||||||||||||||
 A Vatutin | 7 | 6 | A Vatutin | 6 | 4 | 1 | |||||||||||||||||||||
| Q | A Pellegrino | 3 | 4 | WC | M Donati | 2 | 6 | 6 | |||||||||||||||||||
| WC | M Donati | 6 | 6 | WC | M Donati | 4 | 2 | ||||||||||||||||||||
 J Eysseric | 4 | 1 | G García López | 6 | 6 | ||||||||||||||||||||||
| G García López | 6 | 6 | G García López | 6 | 7 | ||||||||||||||||||||||
| WC | J Ocleppo | 5 | 1 | 3 | A Giannessi | 4 | 5 | ||||||||||||||||||||
| 3 | A Giannessi | 7 | 6 | G García López | 6 | 65 | 6 | ||||||||||||||||||||
| 7 | D Brown | 7 | 6 | S Napolitano | 2 | 77 | 3 | ||||||||||||||||||||
| Alt | R Bonadio | 5 | 2 | 7 | D Brown | 4 | 2 | ||||||||||||||||||||
| M Berrettini | 4 | 6 | 2 | S Napolitano | 6 | 6 | |||||||||||||||||||||
| S Napolitano | 6 | 3 | 6 | S Napolitano | 77 | 6 | |||||||||||||||||||||
| K de Schepper | 2 | 2 | Q | A Basso | 62 | 4 | |||||||||||||||||||||
 J Kovalík | 6 | 6 | J Kovalík | 6 | 3 | 4 | |||||||||||||||||||||
| Q | A Basso | 61 | 6 | 77 | Q | A Basso | 3 | 6 | 6 | ||||||||||||||||||
| 2/WC | A Seppi | 77 | 3 | 64 | |||||||||||||||||||||||
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