# 2003 Campionati Internazionali di Sicilia – Singles

Fernando González was the defending champion but did not compete that year.
Nicolás Massú won in the final 1–6, 6–2, 7–6$^{(7–0)}$ against Paul-Henri Mathieu.

## Seeds

A champion seed is indicated in bold text while text in italics indicates the round in which that seed was eliminated.
* Nicolás Massú (champion)
* Nikolay Davydenko (first round)
* David Sánchez (first round)
* Filippo Volandri (second round)
* Paul-Henri Mathieu (final)
* Alberto Martín (semifinals)
* Rubén Ramírez Hidalgo (first round)
* Luis Horna (semifinals)

## 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
| 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 | Final | Final | Final | Final | Final |
| 1 | N Massú | 6 | 6 | | | | | | | | | | | | | | | | | | | | |
| | C Rochus | 4 | 2 | | 1 | N Massú | 6 | 3 | | | | | | | | | | | | | | | |
| | J Acasuso | 6 | 6 | | | J Acasuso | 2 | 1 | r | | | | | | | | | | | | | | |
| Q | J Giner | 3 | 2 | | | | | | | 1 | N Massú | 6 | 1 | 6 | | | | | | | | | |
| | M Vassallo Argüello | 3 | 4 | | | | | | | | A Montañés | 4 | 6 | 4 | | | | | | | | | |
| | T Behrend | 6 | 6 | | | T Behrend | 0 | 4 | | | | | | | | | | | | | | | |
| | A Montañés | 6 | 6 | | | A Montañés | 6 | 6 | | | | | | | | | | | | | | | |
| 7 | R Ramírez Hidalgo | 2 | 4 | | | | | | | | | | | | 1 | N Massú | 6 | 6 | | | | | |
| 3 | D Sánchez | 2 | 6 | 6$^8$ | | | | | | | | | | | 8 | L Horna | 2 | 2 | | | | | |
| | Ó Hernández | 6 | 0 | 7$^{10}$ | | Ó Hernández | 7$^7$ | 6 | | | | | | | | | | | | | | | |
| | I Labadze | 0 | 2 | | Q | T Tenconi | 6$^3$ | 3 | | | | | | | | | | | | | | | |
| Q | T Tenconi | 6 | 6 | | | | | | | | Ó Hernández | 6 | 6$^7$ | 1 | | | | | | | | | |
| | J Melzer | 2 | 6 | 4 | | | | | | 8 | L Horna | 3 | 7$^9$ | 6 | | | | | | | | | |
| | M Puerta | 6 | 4 | 6 | | M Puerta | 4 | 2 | | | | | | | | | | | | | | | |
| | A Pavel | 6$^6$ | 5 | | 8 | L Horna | 6 | 6 | | | | | | | | | | | | | | | |
| 8 | L Horna | 7$^8$ | 7 | | | | | | | | | | | | | | | | 1 | Nicolás Massú | 1 | 6 | 7$^7$ |
| 6 | A Martín | 7$^7$ | 6 | | | | | | | | | | | | | | | | 5 | Paul-Henri Mathieu | 6 | 2 | 6$^0$ |
| | D Ferrer | 6$^4$ | 2 | | 6 | A Martín | 4 | | | | | | | | | | | | | | | | |
| | K Vliegen | 5 | 5 | | | G Blanco | 0 | r | | | | | | | | | | | | | | | |
| | G Blanco | 7 | 7 | | | | | | | 6 | A Martín | 7$^7$ | 6 | | | | | | | | | | |
| | F Squillari | 6 | 6 | | | | | | | | F Squillari | 6$^3$ | 4 | | | | | | | | | | |
| WC | A di Mauro | 4 | 3 | | | F Squillari | w/o | | | | | | | | | | | | | | | | |
| WC | F Aldi | 2 | 5 | | 4 | F Volandri | | | | | | | | | | | | | | | | | |
| 4 | F Volandri | 6 | 7 | | | | | | | | | | | | 6 | A Martín | 6$^5$ | 6$^5$ | | | | | |
| 5 | P-H Mathieu | 4 | 6 | 7$^7$ | | | | | | | | | | | 5 | P-H Mathieu | 7$^7$ | 7$^7$ | | | | | |
| | A Portas | 6 | 3 | 6$^5$ | 5 | P-H Mathieu | 7$^8$ | 3 | 6 | | | | | | | | | | | | | | |
| WC | À Corretja | 1 | r | | Q | N Almagro | 6$^6$ | 6 | 3 | | | | | | | | | | | | | | |
| Q | N Almagro | 3 | | | | | | | | 5 | P-H Mathieu | 4 | 7$^7$ | 6 | | | | | | | | | |
| | V Hănescu | 6 | 6 | | | | | | | Q | D Veronelli | 6 | 6$^5$ | 3 | | | | | | | | | |
| | I Andreev | 3 | 3 | | | V Hănescu | 4 | 2 | | | | | | | | | | | | | | | |
| Q | D Veronelli | 6 | 6 | | Q | D Veronelli | 6 | 6 | | | | | | | | | | | | | | | |
| 2 | N Davydenko | 4 | 4 | | | | | | | | | | | | | | | | | | | | |