# 2023 BOSS Open – Singles

Frances Tiafoe defeated Jan-Lennard Struff in the final, 4–6, 7–6$^{(7–1)}$, 7–6$^{(10–8)}$ to win the singles title at the 2023 Stuttgart Open. It was his third ATP Tour title, and his first on grass courts (following titles on hardcourts and clay courts). Tiafoe saved a championship point en route to the title, in the final-set tiebreak. By winning the title, Tiafoe debuted in the top ten of the ATP rankings for the first time in his career.
Matteo Berrettini was the defending champion, but lost in the first round to Lorenzo Sonego.

## Seeds

The top four seeds received a bye into the second round.
* Stefanos Tsitsipas (second round)
* Taylor Fritz (quarterfinals)
* Frances Tiafoe (champion)
* Hubert Hurkacz (semifinals)
* Tommy Paul (second round)
* Lorenzo Musetti (quarterfinals)
* Matteo Berrettini (first round)
* Nick Kyrgios (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 | Semifinals | Final | Final | Final | Final | Final |
| | Jan-Lennard Struff | 3 | 6 | 6 | | | | | |
| 4 | Hubert Hurkacz | 6 | 3 | 3 | | | | | |
| 4 | Hubert Hurkacz | 6 | 3 | 3 | | Jan-Lennard Struff | 6 | 6$^1$ | 6$^8$ |
| | | | | | 3 | Frances Tiafoe | 4 | 7$^7$ | 7$^{10}$ |
| 3 | Frances Tiafoe | 6 | 7$^{13}$ | | 3 | Frances Tiafoe | 4 | 7$^7$ | 7$^{10}$ |
| Q | Márton Fucsovics | 3 | 6$^{11}$ | | | | | | |

### Top half

| 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 | Semifinals | Semifinals |
| | | | | 1/WC | S Tsitsipas | 6$^8$ | 6 | 5 | | | | | | | | | |
| | R Gasquet | 7$^7$ | 6 | | R Gasquet | 7$^{10}$ | 2 | 7 | | | | | | | | | |
| Q | C Eubanks | 6$^2$ | 4 | | | | | | | R Gasquet | 4 | 5 | | | | | |
| | Z Zhang | 1 | 4 | | | | | | | J-L Struff | 6 | 7 | | | | | |
| | J-L Struff | 6 | 6 | | J-L Struff | 7$^7$ | 7$^7$ | | | | | | | | | | |
| | B Bonzi | 3 | 4 | 5 | T Paul | 6$^4$ | 6$^5$ | | | | | | | | | | |
| 5 | T Paul | 6 | 6 | | | | | | | | | | | J-L Struff | 3 | 6 | 6 |
| | | | | | | | | | | | | | 4 | H Hurkacz | 6 | 3 | 3 |
| | | | | 4 | H Hurkacz | 4 | 7$^7$ | 7$^7$ | | | | | | | | | |
| WC | F López | 6$^5$ | 3 | Q | Y Watanuki | 6 | 6$^5$ | 6$^5$ | | | | | | | | | |
| Q | Y Watanuki | 7$^7$ | 6 | | | | | | 4 | H Hurkacz | 6 | 6 | | | | | |
| | C O'Connell | 6 | 6 | | | | | | | C O'Connell | 4 | 4 | | | | | |
| | D Altmaier | 3 | 1 | | C O'Connell | 7$^7$ | 6 | | | | | | | | | | |
| | L Sonego | 6 | 6 | | L Sonego | 6$^5$ | 3 | | | | | | | | | | |
| 7 | M Berrettini | 1 | 2 | | | | | | | | | | | | | | |

### 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 |
| 6 | L Musetti | 7$^7$ | 6 | | | | | | | | | | | | | | | |
| Q | B Gojo | 6$^4$ | 3 | | 6 | L Musetti | 6 | 6 | | | | | | | | | | |
| | G Barrère | 6 | 6 | | | G Barrère | 3 | 3 | | | | | | | | | | |
| WC | O Otte | 4 | 3 | | | | | | | 6 | L Musetti | 7$^8$ | 6$^4$ | 2 | | | | |
| | M Giron | 6 | 3 | 4 | | | | | | 3 | F Tiafoe | 6$^6$ | 7$^7$ | 6 | | | | |
| | J Lehečka | 4 | 6 | 6 | | J Lehečka | 6$^2$ | 4 | | | | | | | | | | |
| | | | | | 3 | F Tiafoe | 7$^7$ | 6 | | | | | | | | | | |
| | | | | | | | | | | | | | | | 3 | F Tiafoe | 6 | 7$^{13}$ |
| 8 | N Kyrgios | 5 | 3 | | | | | | | | | | | | Q | M Fucsovics | 3 | 6$^{11}$ |
| | Y Wu | 7 | 6 | | | Y Wu | 4 | 6 | 4 | | | | | | | | | |
| | D Shapovalov | 6 | 3 | 4 | Q | M Fucsovics | 6 | 4 | 6 | | | | | | | | | |
| Q | M Fucsovics | 3 | 6 | 6 | | | | | | Q | M Fucsovics | 6 | 7 | | | | | |
| | C Moutet | 6$^0$ | 7$^{10}$ | 5 | | | | | | 2 | T Fritz | 4 | 5 | | | | | |
| | A Karatsev | 7$^7$ | 6$^8$ | 7 | | A Karatsev | 6$^4$ | 3 | | | | | | | | | | |
| | | | | | 2 | T Fritz | 7$^7$ | 6 | | | | | | | | | | |

## Qualifying
### Seeds

* Christopher Eubanks (qualified)
* Márton Fucsovics (qualified)
* Roman Safiullin (first round)
* Borna Gojo (qualified)
* Radu Albot (qualifying competition)
* Yosuke Watanuki (qualified)
* Antoine Bellier (qualifying competition)
* Altuğ Çelikbilek (qualifying competition)

### Qualifiers

* Christopher Eubanks
* Márton Fucsovics
* Yosuke Watanuki
* Borna Gojo

### Qualifying draw
#### First qualifier

| First round | First round | First round | First round | First round | Qualifying competition | Qualifying competition | Qualifying competition | Qualifying competition |
| 1 | Christopher Eubanks | 4 | 6 | 6 | | | | |
| Alt | Benjamin Lock | 6 | 4 | 2 | | | | |
| Alt | Benjamin Lock | 6 | 4 | 2 | 1 | Christopher Eubanks | 7$^7$ | 7$^7$ |
| | | | | | 5 | Radu Albot | 6$^5$ | 6$^3$ |
| Alt | Hugo Gaston | 2 | 0 | | 5 | Radu Albot | 6$^5$ | 6$^3$ |
| 5 | Radu Albot | 6 | 6 | | | | | |

#### Second qualifier

| First round | First round | First round | First round | Qualifying competition | Qualifying competition | Qualifying competition | Qualifying competition |
| 2 | Márton Fucsovics | 6 | 6 | | | | |
| | Louis Wessels | 3 | 1 | | | | |
| | Louis Wessels | 3 | 1 | 2 | Márton Fucsovics | 6 | 6 |
| | | | | 8 | Altuğ Çelikbilek | 4 | 4 |
| Alt | Max Hans Rehberg | 1 | 4 | 8 | Altuğ Çelikbilek | 4 | 4 |
| 8 | Altuğ Çelikbilek | 6 | 6 | | | | |

#### Third qualifier

| First round | First round | First round | First round | First round | Qualifying competition | Qualifying competition | Qualifying competition | Qualifying competition |
| 3 | Roman Safiullin | 6$^5$ | 4 | | | | | |
| | Benjamin Hassan | 7$^7$ | 6 | | | | | |
| | Benjamin Hassan | 7$^7$ | 6 | | | Benjamin Hassan | 5 | 4 |
| | | | | | 6 | Yosuke Watanuki | 7 | 6 |
| | Henri Squire | 6 | 5 | 3 | 6 | Yosuke Watanuki | 7 | 6 |
| 6 | Yosuke Watanuki | 4 | 7 | 6 | | | | |

#### Fourth qualifier

| First round | First round | First round | First round | First round | Qualifying competition | Qualifying competition | Qualifying competition | Qualifying competition | Qualifying competition |
| 4 | Borna Gojo | 6$^4$ | 6 | 6 | | | | | |
| Alt | Mats Rosenkranz | 7$^7$ | 4 | 4 | | | | | |
| Alt | Mats Rosenkranz | 7$^7$ | 4 | 4 | 4 | Borna Gojo | 5 | 7$^7$ | 6 |
| | | | | | 7 | Antoine Bellier | 7 | 6$^2$ | 4 |
| | Vladyslav Orlov | 3 | 4 | | 7 | Antoine Bellier | 7 | 6$^2$ | 4 |
| 7 | Antoine Bellier | 6 | 6 | | | | | | |