Two goals in the final 13 minutes saw Deportivo La Coruna come from behind to stun La Liga leaders Barcelona in a 2-2 draw at Camp Nou.
Deportivo were the last side to deny the champions a home league win on the final day of last season and they kept the hosts frustrated early on before Lionel Messi's brilliant free-kick broke the deadlock.
Jonathan Rodriguez spurned a couple of half-chances on the break, but Barca's second goal looked inevitable, even after Luis Suarez's second-half finish was ruled out for a marginal offside.
Ivan Rakitic duly doubled the lead with a ferocious strike just past the hour mark as Barca began to cruise to what seemed an ultimately straightforward victory.
But Deportivo, who have lost just once away from home so far this season, grabbed a lifeline through top scorer Lucas Perez in the 77th minute and he set up Alex Bergantinos to rifle in an equaliser with just four minutes to play.
Atletico Madrid and rivals Real will now hope to capitalise on Barca's slip-up when they take on Athletic Bilbao and Villarreal respectively on Sunday.
Suarez volleyed wide and Messi saw a free-kick saved as Barca controlled the opening quarter, but Claudio Bravo was called upon to make a smart stop at his near post after Jonathan raced through on the break for Deportivo.
Messi drew another good stop from German Lux with a curling effort before Suarez headed a Dani Alves cross over as Barca kept the visitors pinned in their own half.
But Lux could do nothing to prevent Messi giving the home side the lead six minutes before the break, as the Argentina captain curled a stunning free-kick into the top corner from an almost identical position to his earlier saved effort.
Deportivo began the second half much more brightly, with Jonathan missing two presentable openings, but the visitors had another let-off as Andres Iniesta's clipped cross came back off the crossbar.
Suarez's tap-in was ruled out for offside, but Rakitic gave Barca the cushion they wanted after 62 minutes, blasting the ball into the bottom-right corner having been given time and space 20 yards out.
Messi released Suarez for a third, but the Uruguay striker's poked effort was saved comfortably by Lux, before substitute Cardoso fired wide following another break.
Deportivo themselves had a goal ruled out after Lucas Perez headed in a rebound only to see the offside flag raised, but hopes of a comeback were kindled in the closing stages as the 27-year-old placed a shot past Bravo following Cardoso's throughball into the box.
Faycal Fajr curled wide from distance, but Bergantinos swept a superb shot from the right of the area beyond Bravo's despairing dive following another fast break led by Perez, with Barca held to just a second league draw of the season in dramatic fashion.
