# 2003 Mercedes-Benz Cup – Singles

Andre Agassi was the defending champion but did not compete that year.
Wayne Ferreira won in the final 6–3, 4–6, 7–5 against Lleyton Hewitt.

## Seeds

* Lleyton Hewitt (final)
* Sébastien Grosjean (quarterfinals)
* Sjeng Schalken (second round)
* Gustavo Kuerten (quarterfinals)
* Mark Philippoussis (semifinals)
* Marat Safin (first round)
* Wayne Ferreira (champion)
* Vince Spadea (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 | Final | Final | Final | Final | Final |
| 1 | Lleyton Hewitt | 6 | 6 | | | | | |
| | Nicolas Kiefer | 2 | 4 | | | | | |
| | Nicolas Kiefer | 2 | 4 | 1 | Lleyton Hewitt | 3 | 6 | 5 |
| | | | | 7 | Wayne Ferreira | 6 | 4 | 7 |
| 5 | Mark Philippoussis | 4 | 5 | 7 | Wayne Ferreira | 6 | 4 | 7 |
| 7 | Wayne Ferreira | 6 | 7 | | | | | |

### Top 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 |
| 1 | L Hewitt | 6 | 7 | | | | | | | | | | | | | | | |
| | C Mamiit | 0 | 5 | | 1 | L Hewitt | 6 | 6 | | | | | | | | | | |
| WC | M Joyce | 7$^7$ | 2 | 7$^7$ | WC | M Joyce | 3 | 0 | | | | | | | | | | |
| | J-M Gambill | 6$^5$ | 6 | 6$^4$ | | | | | | 1 | L Hewitt | 6$^3$ | 6 | 6 | | | | |
| | K Carlsen | 6 | 4 | 7$^7$ | | | | | | | K Carlsen | 7$^7$ | 4 | 3 | | | | |
| WC | B Reynolds | 2 | 6 | 6$^3$ | | K Carlsen | 6 | 6 | | | | | | | | | | |
| WC | P Amritraj | 5 | | | WC | P Amritraj | 4 | 2 | | | | | | | | | | |
| 6 | M Safin | 3$^r$ | | | | | | | | | | | | | 1 | L Hewitt | 6 | 6 |
| 3 | S Schalken | 6 | 6 | | | | | | | | | | | | | N Kiefer | 2 | 4 |
| Q | D Golovanov | 4 | 4 | | 3 | S Schalken | 4 | 4 | | | | | | | | | | |
| | N Kiefer | 6 | 6 | | | N Kiefer | 6 | 6 | | | | | | | | | | |
| | N Thomann | 1 | 4 | | | | | | | | N Kiefer | 1 | 7 | 6 | | | | |
| | J Vacek | 2 | 6 | 6 | | | | | | 8 | V Spadea | 6 | 5 | 3 | | | | |
| | K Kim | 6 | 1 | 4 | | J Vacek | 5 | 6 | 2 | | | | | | | | | |
| | J Gimelstob | 4 | 3 | | 8 | V Spadea | 7 | 2 | 6 | | | | | | | | | |
| 8 | V Spadea | 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 |
| 5 | M Philippoussis | 6 | 6 | | | | | | | | | | | | | | |
| | A Kennedy | 3 | 2 | | 5 | M Philippoussis | 6 | 6 | | | | | | | | | |
| Q | Z Fleishman | 1 | 1 | | | M Chang | 2 | 4 | | | | | | | | | |
| | M Chang | 6 | 6 | | | | | | 5 | M Philippoussis | 6 | 3 | 7$^7$ | | | | |
| | H-T Lee | 6 | 6$^5$ | 2 | | | | | 4 | G Kuerten | 3 | 6 | 6$^5$ | | | | |
| | E Taino | 3 | 7$^7$ | 6 | | E Taino | 3 | 6$^5$ | | | | | | | | | |
| | F Niemeyer | 6 | 6$^2$ | 4 | 4 | G Kuerten | 6 | 7$^7$ | | | | | | | | | |
| 4 | G Kuerten | 3 | 7$^7$ | 6 | | | | | | | | | | 5 | M Philippoussis | 4 | 5 |
| 7 | W Ferreira | 6 | 6 | | | | | | | | | | | 7 | W Ferreira | 6 | 7 |
| Q | R Yim | 4 | 4 | | 7 | W Ferreira | 7$^7$ | 6 | | | | | | | | | |
| | A Bogomolov Jr. | 6 | 6 | | | A Bogomolov Jr. | 6$^1$ | 3 | | | | | | | | | |
| | R Mello | 3 | 2 | | | | | | 7 | W Ferreira | 7$^7$ | 6$^4$ | 6 | | | | |
| | R Ginepri | 6 | 6 | | | | | | 2 | S Grosjean | 6$^4$ | 7$^7$ | 2 | | | | |
| Q | A Ilie | 1 | 1 | | | R Ginepri | 2 | 3 | | | | | | | | | |
| | X Malisse | 6 | 5 | 3 | 2 | S Grosjean | 6 | 6 | | | | | | | | | |
| 2 | S Grosjean | 4 | 7 | 6 | | | | | | | | | | | | | |