Zubikarai doubled Barcelona's advantage in their 2-0 Copa del Rey semi-final first leg encounter at the Camp Nou when teammate Gorka Elustondo inadvertently fired the ball at him to cap a miserable night for the Basque outfit.
Barça took a controversial lead through Sergio Busquets before they (or rather, Sociedad) sealed victory in comedy fashion after the break.
Busquets rounded off a scrappy move with a neat finish to put Barca ahead - moments after Sociedad had had a decent penalty shout turned down when Carlos Vela appeared to be tugged down by Javier Mascherano. Iñigo Martinez could not hide his frustration and was dismissed for dissent.
And the 10 men did not help themselves after the interval as Elustondo blasted an attempted clearance at the helpless Zubikarai.