Barcelona stumbled for a third straight match in its quest to defend its Spanish league title after losing at Real Sociedad 1-0 on Saturday, letting Atletico Madrid and Real Madrid tighten the race even further.

Mikel Oyarzabal headed in Sociedad's goal in the fifth minute, and goalkeeper Geronimo Rulli protected the lead with two saves of Lionel Messi's late efforts.

Barcelona's failure to win at Anoeta for a sixth consecutive season came after Atletico fought back at Espanyol to win 3-1, and Cristiano Ronaldo led Madrid's 4-0 rout of Eibar.

Two rounds ago, Barcelona was nine points clear after a draw at Villarreal. Now, after losses to Madrid and at Sociedad, Barcelona's lead has dwindled to three points over Atletico and four over Madrid with six rounds left.

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