2003 Copa AT&T – Singles

Nicolás Massú was the defending champion but lost in the first round to Agustín Calleri.

Carlos Moyà won in the final 6–3, 4–6, 6–4 against Guillermo Coria.

Seeds

 * 1) 🇪🇸 Carlos Moyá (champion)
 * 2) 🇦🇷 David Nalbandian (quarterfinals)
 * 3)  Fernando González (second round)
 * 4) 🇦🇷 Gastón Gaudio (semifinals)
 * 5) 🇦🇷 Juan Ignacio Chela (quarterfinals)
 * 6) 🇧🇷 Gustavo Kuerten (semifinals)
 * 7) 🇪🇨 Nicolás Lapentti (second round)
 * 8) 🇦🇷 Guillermo Coria (final)