Only France and Spain had achieved this before. The Cordovan rider won by seven seconds over American Kyle Chaney and finished ninth in the general classification.
Meanwhile, in the Trucks category, Lithuanian Zala Vaidotas won the stage, followed by Czech Ales Loprais and his compatriot Martin Macik.
The Dakar Rally will continue its journey on Monday with Stage 8, which features a 481-kilometer timed section and a 236-kilometer liaison, entirely within Wadi Ad-Dawasir.
"This is a historic day for Argentine motorsport. For the first time in the history of the Dakar Rally, Argentine drivers have won three stages in a single day," the organizers stated.