Second-seeded Albert Montanes of Spain was knocked of the second round of the Brazil Open by Ricardo Mello of Brazil 6-3, 6-3 on Wednesday.
It was Montanes' first match in the clay-court tournament after he received a bye into the second round.
Sixth-seeded Tommy Robredo of Spain, who won the Movistar Open on Sunday in Chile, was also bounced, by countryman Pablo Andujar, 6-4, 5-7, 6-2.
Other seeded players fared better.
Top-seeded Nicolas Almagro of Spain defeated Joao Souza of Brazil 6-2, 6-2, while No. 3 seed Thomaz Bellucci of Brazil beat Carlos Berlocq of Argentina 6-4, 7-5, and No. 4 seed Alexandr Dolgopolov of Ukraine downed Spaniard Ruben Ramirez Hidalgo 7-5, 6-4.
Fifth-seeded Juan Ignacio Chela of Argentina also reached the quarterfinals, beating Lukasz Kobot of Poland, 3-6, 7-5, 6-3, and No. 7 Potito Starace of Italy was a winner over Leonardo Mayer of Argentina 6-4, 7-6 (9).
In another match, Rui Machado of Portugal defeated Filippo Volandri of Italy 6-2, 6-1.
