Andres Iniesta has revealed his dissatisfaction after Barcelona missed the chance to go top of La Liga on Sunday evening.
Real Madrid's 2-1 defeat at Valencia meant that victory for Barca at Real Sociedad would see the Catalan outfit return to the summit.
However, Luis Enrique's side lost at the Anoeta for the fourth time in five seasons.
"We had chances to score a goal but we couldn't. The team played well, with good rhythm. We failed to score," Iniesta told reporters.
"Apart from the own goal, we didn't have the same feeling as we had on other occasions, where we lost control. It's a shame because it was the perfect opportunity to close the points gap."
Real Madrid remain top of La Liga on 39 points.