Berlocq crushed Bjorn Phau 6-1, 6-0 and Lopez fought off Paolo Lorenzi 6-4, 7-6 (7-4) to set up a third-round meeting.
The first round was completed with victories by a pair of Americans. Ryan Harrison advanced with a 4-6, 6-3, 6-4 decision over Alex Bogomolov and Bobby Reynolds moved on by ousting Ivo Karlovic 7-6 (7-5), 2-6, 6-3.
Kevin Anderson also reached the second round with a 6-3, 6-4 decision over Joao Souza and will next meet American Sam Querrey.
Mardy Fish and John Isner, the top two Americans in the world rankings, will see their first action of the tournament on Thursday.
Fish, seeded No. 1 in this event, will face Michael Russell, and the second-seeded Isner will take on Horacio Zeballos.