Atletico Madrid lost ground in LaLiga's title race as two second-half penalties from Real Sociedad condemned them to a 2-0 defeat at the Estadio Anoeta.
Diego Simeone's men had the chance to go above Real Madrid and Barcelona, if only for the evening, but failed to seize it as Sociedad secured a third straight win and moved level on points with fifth-placed Villarreal.
Kevin Gameiro clipped a shot against a post from a lightning counter-attack in the 28th minute, but Sociedad were more than a match for Atleti and took the lead when Carlos Vela calmly placed a penalty past Jan Oblak after Gabi had fouled Yuri in the box.
Willian Jose fired in a second spot-kick with 15 minutes left after Vela twisted and turned his way into the box, as Simeone's men suffered a second LaLiga defeat in their last three matches.