# 2003 Grand Prix de Tennis de Lyon – Singles

Paul-Henri Mathieu was the defending champion but lost in the first round to Rainer Schüttler.
Schüttler won in the final 7–5, 6–3 against Arnaud Clément.

## Seeds

* Rainer Schüttler (champion)
* Sébastien Grosjean (first round)
* Paradorn Srichaphan (semifinals)
* Félix Mantilla (first round)
* Mardy Fish (first round)
* Wayne Ferreira (first round)
* Marat Safin (first round)
* Yevgeny Kafelnikov (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 |
| 1 | Rainer Schüttler | 6 | 3 | 7 | | | | |
| | Mikhail Youzhny | 3 | 6 | 5 | | | | |
| | Mikhail Youzhny | 3 | 6 | 5 | 1 | Rainer Schüttler | 7 | 6 |
| | | | | | | Arnaud Clément | 5 | 3 |
| 3 | Paradorn Srichaphan | 2 | 3 | | | Arnaud Clément | 5 | 3 |
| | Arnaud Clément | 6 | 6 | | | | | |

### 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 | Semifinals | Semifinals | Semifinals | Semifinals | Semifinals |
| 1 | R Schüttler | 6 | 6 | | | | | | | | | | | | | | | |
| | P-H Mathieu | 2 | 2 | | 1 | R Schüttler | 4 | 7$^7$ | 7 | | | | | | | | | |
| | N Lapentti | 2 | 6$^3$ | | | I Ljubičić | 6 | 6$^2$ | 5 | | | | | | | | | |
| | I Ljubičić | 6 | 7$^7$ | | | | | | | 1 | R Schüttler | 7$^7$ | 6 | | | | | |
| Q | X Malisse | 5 | 6 | 6 | | | | | | Q | X Malisse | 6$^2$ | 4 | | | | | |
| SE | A Pavel | 7 | 3 | 4 | Q | X Malisse | 6 | 6 | | | | | | | | | | |
| Q | T Enqvist | 7$^9$ | 7$^7$ | | Q | T Enqvist | 3 | 4 | | | | | | | | | | |
| 6 | W Ferreira | 6$^7$ | 6$^3$ | | | | | | | | | | | 1 | R Schüttler | 6 | 3 | 7 |
| 4 | F Mantilla | 3 | 6$^2$ | | | | | | | | | | | | M Youzhny | 3 | 6 | 5 |
| | M Youzhny | 6 | 7$^7$ | | | M Youzhny | 1 | 7$^7$ | 6 | | | | | | | | | |
| | R Nadal | 3 | 5 | | | D Hrbatý | 6 | 6$^1$ | 2 | | | | | | | | | |
| | D Hrbatý | 6 | 7 | | | | | | | | M Youzhny | 7$^7$ | 6 | | | | | |
| | R Sluiter | 6$^5$ | 3 | | | | | | | | R Ginepri | 6$^3$ | 2 | | | | | |
| | R Ginepri | 7$^7$ | 6 | | | R Ginepri | 4 | 6 | 6 | | | | | | | | | |
| SE | C Saulnier | 7 | 6 | | SE | C Saulnier | 6 | 3 | 4 | | | | | | | | | |
| 5 | M Fish | 5 | 3 | | | | | | | | | | | | | | | |

### 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 |
| 7 | M Safin | 1 | 4 | | | | | | | | | | | | | | | |
| | F Santoro | 6 | 6 | | | F Santoro | 6 | 5 | 6 | | | | | | | | | |
| WC | À Corretja | 6$^3$ | 6$^5$ | | Q | M Rosset | 3 | 7 | 4 | | | | | | | | | |
| Q | M Rosset | 7$^7$ | 7$^7$ | | | | | | | | F Santoro | 6 | 3 | 6$^4$ | | | | |
| | O Rochus | 3 | 7$^7$ | 6 | | | | | | 3 | P Srichaphan | 1 | 6 | 7$^7$ | | | | |
| WC | T Ascione | 6 | 6$^4$ | 3 | | O Rochus | 3 | 2 | | | | | | | | | | |
| | D Sánchez | 1 | 1 | | 3 | P Srichaphan | 6 | 6 | | | | | | | | | | |
| 3 | P Srichaphan | 6 | 6 | | | | | | | | | | | | 3 | P Srichaphan | 2 | 3 |
| 8 | Y Kafelnikov | 2 | 3 | | | | | | | | | | | | | A Clément | 6 | 6 |
| | F Vicente | 6 | 6 | | | F Vicente | 1 | 4 | | | | | | | | | | |
| | A Clément | 6 | 6 | | | A Clément | 6 | 6 | | | | | | | | | | |
| | F Saretta | 3 | 4 | | | | | | | | A Clément | 6 | 6 | | | | | |
| Q | H Arazi | 6$^7$ | 7 | 7$^7$ | | | | | | Q | H Arazi | 3 | 4 | | | | | |
| | R Štěpánek | 7$^9$ | 5 | 6$^5$ | Q | H Arazi | 6 | 6 | | | | | | | | | | |
| WC | N Mahut | 4 | 6 | r | WC | N Mahut | 2 | 4 | | | | | | | | | | |
| 2 | S Grosjean | 6 | 3 | | | | | | | | | | | | | | | |