Villarreal condemned Barcelona to their first defeat of the campaign with an impressive 3-1 home win to go second in the Primera Liga on Saturday.
Manuel Pellegrini's side beat Barca at their own game, controlling possession with some slick passing, and raced into a two-goal lead inside 13 minutes through Santi Cazorla and a Marcos Senna penalty.
Barcelona's 17-year-old forward Bojan Krkic, in his first start, pulled one back in the 25th but Senna netted a second penalty before the break.
Villarreal, who were unlucky not score more goals, now have 18 points from eight games. They are a point adrift of leaders Real Madrid who were playing at Espanyol in Saturday's late game. Barca slipped to fourth with 17.
Valencia cruised to a 4-2 win at Deportivo Coruna with two headers from striker Fernando Morientes to go third, also with 18 points.
Sevilla returned to winning ways after four consecutive league defeats with a comfortable 2-0 win at bottom club Levante.
Brazilian striker Luis Fabiano scored both goals in the first 14 minutes to spoil Italian coach Giovanni De Biasi's debut on the bench for the home side.
DEFT BACKHEEL
Barcelona had barely touched the ball when Villarreal took the lead in the Madrigal with a well-worked move down the left in the third minute.
Cazorla passed to Guillermo Franco on the edge of the area and carried on to pick up the Mexican's deft backheel before sweeping a curling shot past Victor Valdes.
The home side continued to pile forward and won a penalty, when Eric Abidal brought down Robert Pires, which Senna put away.
Barca came back when Lionel Messi's pass allowed Bojan, starting in place of Ronaldinho who was rested, to get behind his marker and fire in off the near post.
While there were some doubts about the first penalty, the second was clear when Gabriel Milito took Pires's legs as he raced into the area and the Argentine was lucky to remain on the pitch. Senna scored again from the spot in the 34th.
Coach Frank Rijkaard went for all-out attack after the break bringing on forward Giovani dos Santos for defender Oleguer but it was Villarreal who continued to pose the greater threat.
Barcelona lost Portugal midfielder Deco to a thigh injury near the end.