The Real Madrid forward had also sent Portugal ahead with a penalty in the fourth minute, and Pique has seemingly had a dig at Ronaldo for going down under minimal contact from his club teammate Nacho inside the box.
"We had more chances, they had three shots on goal, and scored three goals. Matches go a certain way and you have to face up to it," Pique told reporters.
"To see yourself in the first game of a World Cup go behind to a penalty after two minutes, you have to have a good feeling after how the game went. Ronaldo has a habit of throwing himself to the ground."
Next up for Portugal is a clash with Morocco on Wednesday, while Spain will take on Iran.