Real Madrid continued their disastrous start to the La Liga campaign with a 1-0 home loss against Real Betis on Wednesday.
Cristiano Ronaldo started up front, but couldn't provide the breakthrough Los Blancos required as Zinedine Zidane's men suffered their first defeat from five opening league fixtures.
Second-half substitute Borja Mayoral nearly fired the home side ahead late, with a sensational back-heel of Dani Carvajal's cross from the right, but Betis keeper Antonio Adan did enough to parry his low shot off the crossbar to keep the scoreline level.
Betis thought they'd snatched a late winner in the 90th minute, but the goal was rightfully ruled offside, much to the visitors' dismay.
But they were celebrating four minutes later, when Antonio Sanabria headed home Antonio Barragan's inch-perfect cross past a helpless Keylor Navas from close range.
The defending champions have now taken just eight points from five matches on the young season. They are seven points behind leaders Barcelona, who throttled Eibar 6-1 on Tuesday.
Angel Correa and Yannick Carrasco scored second-half goals as Atletico Madrid extended their unbeaten league start to five matches with a 2-1 win at Athletic Bilbao.
Atletico, unbeaten in six games in all competitions this season, broke the deadlock through Correa 10 minutes into the second half and Carrasco added a second in the 73rd minute.
Bilbao, who slipped to a first home defeat of the season, squandered a first-half penalty when Aritz Aduriz's spot kick, for Filipe Luis' foul on Raul Garcia, was saved by Jan Oblak.
Bilbao midfielder Garcia struck a late consolation for the Basque side in the second minute of time added on.
Portuguese defender Luisinho's solitary goal clinched Deportivo La Coruna a 1-0 home win against fellow strugglers Alaves.