Moments after Jonathas gave the visitors the lead from a Carlos Vela pass, the Mexican forward turned scorer as Vela performed a stunning chip to double the lead for La Real.
Diego Reyes also enjoyed an excellent day, and with the score at 3-0 in the second half, the gold medalist headed home from a Ruben Pardo corner for the 4-0.
Reyes would subsequently leave the game injured in the 70th minute but it was a solid performance in the midfield from the Mexican international.
The final result moved Real Sociedad six points clear from La Liga's relegation zone and next will take on Granada for matchday 24.
You can watch highlights of Real Sociedad's win below: