Real Sociedad scored twice after Gerard Piqué was sent off ten minutes in to the second half to pull off the massive upset of Barcelona.
Minutes after just missing a great chance after breaking Sociedad's offside trap, Lionel Messi put Barcelona ahead 1-0. Soceidad goalkeeper Claudio Bravo was the root of the evil, sending a clearance right to Andrés Iniesta who wasted no time crossing the ball in to the center of the pitch. Cesc Fábregas put a light touch on the ball, directing it to Messi who danced around a Sociedad defender and beat Bravo with a soft shot.
Sociedad nearly equalized in the 12th minute on a free kick. Rather than the usual attempt on goal, Gonzalo Castro sent a short ball to Xabi Prieto who timed his run perfectly off the free kick. Jordi Alba recovered excellently, nearly cutting off Prieto but his effort helped cut down his angle and Prieto's shot went harmlessly in to the side netting.
Despite some close calls for Sociedad, they simply couldn't slow down the Barcelona attack. In the 25th minute Xavi send a ball over the top to Dani Alves who settled it quickly before finding Pedro Rodriguez behind Bravo for an easy tap-in to make it 2-0.
Sociedad pulled a goal back right before halftime after an initial cross was blocked and popped up in the air at the top of the Barcelona box. Antoine Griezmann headed down the ball to Carlos Vela who moved it wide to Castro who took a touch and placed a pinpoint shot past Victor Valdés hand in to the far corner.
Sociedad kept up the pressure in the second half and things turned in their advantage in the 55th minute when defender Gerard Piqué brought down Vela and earned his second yellow card of the match and the corresponding marching orders that come with a red card.
They were quick to take advantage finding an equalizer in the 62nd minute. Castro's shot from the left side of the box deflected off Javier Mascherno and Valdes was only able to get his fingertips on the ball, not enough to prevent it from finding the back of the net and pulling Sociedad even at 2-2.
Barceland appeared to be on their way to at least holding on for the draw but Sociedad wasn't done. Imanol Agirretxe finished a Carlos Martinez cross one minute in to stoppage time to give Sociedad the unlikely victory.
It's Barcelona's first lost in La Liga this season while Sociedad leaps up to fifth place in the table for the moment.