2004 Siebel Open – Singles

Andre Agassi was the defending champion but lost in the semifinals to Mardy Fish.

Andy Roddick won in the final 7–6(15–13), 6–4 against Fish.

Seeds
A champion seed is indicated in bold text while text in italics indicates the round in which that seed was eliminated.


 * 1) 🇺🇸 Andy Roddick (champion)
 * 2) 🇺🇸 Andre Agassi (semifinals)
 * 3) 🇺🇸 Mardy Fish (final)
 * 4) 🇺🇸 Taylor Dent (second round)
 * 5) 🇺🇸 Robby Ginepri (second round)
 * 6) 🇺🇸 Vince Spadea (second round)
 * 7) 🇺🇸 James Blake (second round)
 * 8)  Wayne Ferreira (first round)