The full-back was part of the fightback after Barca went one goal down early, by curling home a superb equaliser to put his team back into the game.
He also played a part in the winning goal, his low cross being deflected into the path of Frenkie de Jong to score what proved to be the winning goal.
And speaking to La Liga TV after the match, Alba was keen to stress just how well Barca had played against a Real Sociedad side that had started the season in good form.
He said: "[This was] The best of the whole year due to the desire and attitude. We have all gone together, and saw a Barca wanting to have a great game. We have fought each ball as if it were the last, and we have known how to suffer.
"The attitude was fundamental. We played against a great team. In the first half we had more of the ball and we played better, but in the second half we managed to hold on.
"Real Sociedad are one of the best teams in La Liga. This game has to give us confidence to continue scoring points, and fight LaLiga until the end."
Barcelona's victory has moved them into the top five in La Liga and just six points off the top the table with games in hand over their rivals above them.