| Singles | |
|---|---|
| 2004 Brasil Open | |
| Champion |  Gustavo Kuerten |
| Runner-up |  Agustín Calleri |
| Score | 3–6, 6–2, 6–3 |
Sjeng Schalken was the defending champion but did not compete that year.
Gustavo Kuerten won in the final 3–6, 6–2, 6–3 against Agustín Calleri.
Carlos Moyá (first round)
Nicolás Massú (first round) Gustavo Kuerten (champion) Agustín Calleri (final) Mariano Zabaleta (first round) Félix Mantilla (first round) Gastón Gaudio (second round) Juan Ignacio Chela (quarterfinals)| Semifinals | Final | ||||||||||||
| José Acasuso | 4 | 3 | |||||||||||
| 3 | Gustavo Kuerten | 6 | 6 | ||||||||||
| 3 | Gustavo Kuerten | 3 | 6 | 6 | |||||||||
| 4 | Agustín Calleri | 6 | 2 | 3 | |||||||||
| 4 | Agustín Calleri | 6 | 5 | 6 | |||||||||
 Luis Horna | 4 | 7 | 1 | ||||||||||
| First round | Second round | Quarterfinals | Semifinals | ||||||||||||||||||||||||
| 1 | C Moyá | 3 | 3 | ||||||||||||||||||||||||
 T Behrend | 6 | 6 | T Behrend | 6 | 6 | ||||||||||||||||||||||
 H Levy | 4 | 63 | R Ramírez Hidalgo | 2 | 2 | ||||||||||||||||||||||
| R Ramírez Hidalgo | 6 | 77 | T Behrend | 6 | 2 | 4 | |||||||||||||||||||||
 C Rochus | 3 | 4 | J Acasuso | 0 | 6 | 6 | |||||||||||||||||||||
| J Acasuso | 6 | 6 | J Acasuso | 77 | 6 | ||||||||||||||||||||||
 F Volandri | 6 | 6 | F Volandri | 64 | 2 | ||||||||||||||||||||||
| 6 | F Mantilla | 2 | 2 | J Acasuso | 4 | 3 | |||||||||||||||||||||
| 3 | G Kuerten | 3 | 6 | 6 | 3 | G Kuerten | 6 | 6 | |||||||||||||||||||
| Ó Hernández | 6 | 2 | 3 | 3 | G Kuerten | 77 | 6 | ||||||||||||||||||||
 R Gasquet | 6 | 77 | R Gasquet | 63 | 3 | ||||||||||||||||||||||
| WC | F Ferreiro | 0 | 65 | 3 | G Kuerten | 3 | 7 | 7 | |||||||||||||||||||
| Q | F Squillari | 6 | 7 | Q | F Squillari | 6 | 5 | 5 | |||||||||||||||||||
| Q | J-R Lisnard | 2 | 5 | Q | F Squillari | 77 | 6 | ||||||||||||||||||||
| WC | R Mello | 2 | 4 | 7 | G Gaudio | 63 | 3 | ||||||||||||||||||||
| 7 | G Gaudio | 6 | 6 | ||||||||||||||||||||||||
| First round | Second round | Quarterfinals | Semifinals | ||||||||||||||||||||||||
| 8 | J I Chela | 6 | 6 | ||||||||||||||||||||||||
| F Saretta | 2 | 2 | 8 | J I Chela | 6 | 6 | |||||||||||||||||||||
| D Ferrer | 6 | 5 | D Ferrer | 2 | 4 | ||||||||||||||||||||||
 N Lapentti | 4 | 2r | 8 | J I Chela | 3 | 6 | 3 | ||||||||||||||||||||
| G Cañas | 1 | 0r | 4 | A Calleri | 6 | 3 | 6 | ||||||||||||||||||||
| Q | F Verdasco | 6 | 1 | Q | F Verdasco | 4 | 4 | ||||||||||||||||||||
| A Portas | 1 | 3 | 4 | A Calleri | 6 | 6 | |||||||||||||||||||||
| 4 | A Calleri | 6 | 6 | 4 | A Calleri | 6 | 5 | 6 | |||||||||||||||||||
| 5 | M Zabaleta | 4 | 1 | L Horna | 4 | 7 | 1 | ||||||||||||||||||||
| A Montañés | 6 | 6 | A Montañés | 2 | 64 | ||||||||||||||||||||||
| D Sánchez | 2 | 64 | G Blanco | 6 | 77 | ||||||||||||||||||||||
| G Blanco | 6 | 77 | G Blanco | 1 | 65 | ||||||||||||||||||||||
| WC | P Braga | 3 | 2 | L Horna | 6 | 77 | |||||||||||||||||||||
| L Horna | 6 | 6 | L Horna | 6 | 6 | ||||||||||||||||||||||
| Q | J Mónaco | 6 | 6 | Q | J Mónaco | 4 | 1 | ||||||||||||||||||||
| 2 | N Massú | 4 | 2 | ||||||||||||||||||||||||
Roger Federer defeated Marat Safin in the final, 7–6(7–3), 6–4, 6–2 to win the men's singles tennis title at the 2004 Australian Open. It was his first Australian Open title and second major title overall. With the win, Federer gained the world No. 1 ranking for the first time in his career, and would hold the position for a record 237 consecutive weeks.
Juan Carlos Ferrero defeated Martin Verkerk in the final, 6–1, 6–3, 6–2 to win the men's singles tennis title at the 2003 French Open. It was his first and only major singles title.
Andy Roddick defeated Juan Carlos Ferrero in the final, 6–3, 7–6(7–2), 6–3 to win the men's singles tennis title at the 2003 US Open. It was his first major title. Roddick remains the most recent American to win a major men's singles title. Roddick saved a match point en route to the title, in the semifinals against David Nalbandian. He also completed the "Summer Slam," having won Masters titles in Canada and Cincinnati in the lead-up to the US Open.
Jan Vacek won in the final 2–6, 7–6(7–2), 6–3 against Fernando Meligeni.
Jan Vacek was the defending champion but did not compete that year.
Gustavo Kuerten was the defending champion but lost in the semifinals to Rainer Schüttler.
Gustavo Kuerten was the defending champion but lost in the first round to Agustín Calleri.
Nicolás Massú was the defending champion but lost in the first round to Agustín Calleri.
Carlos Moyá was the defending champion but lost in the final 6–4, 6–1 against Guillermo Coria.
Gastón Gaudio defeated Jarkko Nieminen in the final, 6–2, 6–3 to win the singles title at the 2002 Majorca Open.
Gustavo Kuerten defeated Hicham Arazi in the final, 6–3, 6–2, 6–4 to win the singles tennis title at the 2001 Monte Carlo Masters.
Guillermo Coria defeated Agustín Calleri in the final, 6–3, 6–4, 6–4 to win the singles tennis title at the 2003 Hamburg European Open.
Juan Carlos Ferrero defeated Nicolás Massú in the final, 6–3, 6–4, 6–3 to win the singles tennis title at the 2003 Madrid Open.
Roger Federer defeated Tim Henman in the final, 6–3, 6–3, to win the men's singles tennis title at the 2004 Indian Wells Masters.
Andy Roddick won the men's singles tennis title at the 2004 Miami Open after Guillermo Coria retired in the final, with the scoreline at 6–7(2–7), 6–3, 6–1.
Carlos Moyá was the defending champion but lost in the quarterfinals to Félix Mantilla.
Paradorn Srichaphan was the defending champion and won in the final 6–2, 6–4 against James Blake.
Agustín Calleri was the defending champion but lost in the first round to Luis Horna.
Carlos Moyá was the defending champion but lost in the third round to Gastón Gaudio.
Gastón Gaudio was the defending singles champion of the Torneo Godó men's tennis tournament, but lost in the quarterfinals this year.