Gonzalez needed just over an hour to eliminate Hidalgo 6-4, 6-3 in a bid to win this clay-court event for the third straight time. Gonzalez had eight aces.
In other second-round action Wednesday, Alberto Martin was a 6-3, 6-4 winner over Richardo Mello, Joao Souza defeated Pere Riba 6-4, 6-4 and Marcel Granollers ousted Lukasz Kubot 6-4, 6-2.
Gonzalez will meet Granollers in the quarterfinals.
UPI horse racing weekend preview
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