Third-seeded Tommy Robredo of Spain reached the quarterfinals of the Copa Claro Wednesday, defeating Guido Pella of Argentina 4-6, 6-1, 6-4.
Fourth-seeded Nicolas Almagro, who beat Horacio Zeballos of Argentina 6-2, 7-5, advanced to the second round of the clay-court tournament.
Almagro has won 12 ATP titles -- all on clay -- and six have come on the annual Latin American swing.
Fifth-seeded Marcel Granollers was upset by fellow Spaniard Pablo Andujar 6-3, 6-0. Andujar reached the quarterfinals.
Eighth-seeded Jeremy Chardy of France advanced to the second round, defeating Alejandro Gonzalez of Colombia 6-4, 7-5.
Other unseeded players advancing to the second round included Alexandr Dolgopolov of Ukraine and Daniel Gimeno-Traver of Spain.