Zaragoza doubled their advantage moments later as the 22-year-old forward again slotted into the net to give the hosts total control.
Barca were given the chance to reduce the arrears when keeper Yassine Bounou conceded a penalty.
However, Sandro Ramirez was unable to capitalise from 12 yards as he sent his spot kick wide of Bounou's goal.
The visitors' misery was compounded five minutes before half time when Pedro Sanchez all but ended the game as a contest by scoring a third.
Real rounded off a triumphant evening when Javi Alamo scored three minutes from time to keep the Aragon outfit in the hunt for a promotion place.