Barcelona conceded a second goal to Getafe forward Angel Lafita in injury time to stumble to a 2-2 draw at home, dealing a major blow to its hopes of defending their Spanish league title.
The match was Barcelona's first home game since former coach Tito Vilanova's death last week from throat cancer.
He was honored with a commemorative video, an enormous banner with the message 'Tito, Always Eternal', and a minute's silence before kickoff.
Lionel Messi volleyed in Dani Alves' pass to open the scoring in the 23rd minute, only for Lafita to level after a rare attack for Getafe.
Substitute Cesc Fabregas appeared to have put Barcelona back on track when he initiated a move that ended with Alexis Sanchez scoring in the 67th minute.
But Barcelona's brittle defence again betrayed them in the final moments when Lafita charged in to head home Julian Gavilan's cross and grab a draw that silenced the Camp Nou.
Out of the Champions League and Copa del Rey, Barcelona's chances of retaining their La Liga title are fading fast.
The Catalan club are left three points behind Atletico Madrid.
Elche moving up
Elche moved a provisional six points above the drop after winning 1-0 at Malaga thanks to Garry Rodrigues' strike.
Elche had two players shown direct red cards.
Reserve goalkeeper Antonio Rodriguez was booked for coming off the bench to argue with Malaga's players in the 68th minute, and defender Alberto Botia was sent off in the 82nd minute for kicking the ball into a prone Malaga player after a foul.