Nikolay Davydenko was the defending champion but lost in the first round to Radek Štěpánek.
Juan Ignacio Chela won in the final 6–7(2–7), 6–3, 6–3 against Marat Safin.
Seeds
Rainer Schüttler (first round) Nicolás Massú (first round) Agustín Calleri (first round) Tommy Robredo (quarterfinals) Juan Ignacio Chela (champion) Max Mirnyi (second round) Gastón Gaudio (first round) Marat Safin (final)
Draw
Finals
Top half
Bottom half
References 2004 Estoril Open draw