'La Roja' found themselves a goal down in the opening minutes after Cristiano Ronaldo converted a penalty he had earnt.
However, they didn't let the setback derail their performance and as they slowly began to grow into the game, Diego Costa looked more of a threat.
That would come to fruition in the 24th minute when the Atletico Madrid striker picked up a loose ball just outside the box.
Shrugging off a few Portuguese defenders, Costa dragged a low shot past Rui Patricio and into the bottom left corner to make it 1-1 in Sochi.
Portugal appealed for a foul on Pepe during the build-up but after a VAR review, the goal stood, much to Spanish supporters delight.