1989 Guarujá Open – Singles

Luiz Mattar was the defending champion and won in the final 7–6, 6–4 against Jimmy Brown.

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


 * 1) 🇧🇷 Luiz Mattar (champion)
 * 2) 🇺🇸 Lawson Duncan (first round)
 * 3) 🇵🇪 Jaime Yzaga (semifinals)
 * 4) 🇧🇷 Cássio Motta (quarterfinals)
 * 5) 🇦🇷 Javier Frana (first round)
 * 6) 🇦🇷 Eduardo Bengoechea (quarterfinals)
 * 7) 🇺🇸 Todd Witsken (quarterfinals)
 * 8) 🇧🇷 Danilo Marcelino (semifinals)