| Men's singles | |
|---|---|
| 2004 Abierto Mexicano Telefonica Movistar | |
| Champion |  Carlos Moyá |
| Runner-up | Fernando Verdasco |
| Score | 6–3, 6–0 |
Agustín Calleri was the defending champion but lost in the first round to Luis Horna.
Carlos Moyá won in the final 6–3, 6–0 against Fernando Verdasco.
A champion seed is indicated in bold text while text in italics indicates the round in which that seed was eliminated.
Carlos Moyá (champion)
Nicolás Massú (quarterfinals)
Agustín Calleri (first round) Mariano Zabaleta (second round) Félix Mantilla Botella (second round) Gastón Gaudio (second round) Juan Ignacio Chela (semifinals)
Filippo Volandri (quarterfinals)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.
Luis Horna was the defending champion, but retired due to a right leg injury, in the first round against Gastón Gaudio.
Guillermo Cañas was the defending champion but chose not to participate that year.
Juan Ignacio Chela was the defending champion, but lost in the second round to Agustín Calleri.
Sjeng Schalken was the defending champion but did not compete that year.
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 was the defending champion, but lost in the second round this year.
Gastón Gaudio was the defending champion but lost in the quarterfinals to Flávio Saretta.
Andre Agassi won the inaugural singles tennis title at the 2002 Madrid Open after Jiří Novák withdrew from the final.
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.
Marcelo Ríos was the defending champion but did not compete that year.
Carlos Moyá was the defending champion and won in the final 6–2, 6–3 against David Ferrer.
Nicolás Lapentti was the defending champion but lost in the third round to Mariano Zabaleta.
Lleyton Hewitt was the defending champion but lost in the quarterfinals to Paradorn Srichaphan.
Carlos Moyá was the defending champion but lost in the quarterfinals to Félix Mantilla.
Carlos Moyá was the defending champion but lost in the third round to Gastón Gaudio.
