World No.3 Marin Cilic of Croatia won his debut match at the ATP’s Rio Open in straight sets.
The clay-court tournament’s top seed beat Argentine Carlos Berlocq 6-3 6-2 to ease into the last 16.
Cilic will meet Gael Monfils or Horacio Zeballos in the next round.
Albert Ramos-Vinolas overcame Brazilian Rogerio Dutra Silva 6-3 3-6 6-4 in their first-round encounter.
The Spanish fourth seed will meet Nicolas Jarry in the round of 16 after the Chilean got past Guillermo Garcia 6-3 7-6 (7-3).
Spaniard Fernando Verdasco, the eighth seed, needed three sets to overcome Argentina’s Leonardo Mayer 6-2 3-6 6-3.
Other first-round winners were American Tennys Sandgren and Portuguese Gastao Elias.