La Liga leaders Barcelona's 125th anniversary celebrations were spoiled by Las Palmas who claimed a shock 2-1 win at Estadi Olimpic Lluis Companys on Saturday after Fabio Silva scored the winner to extend the hosts' winless league run to three games.
Barca remain on 34 points and lead second-placed Real Madrid by four but their rivals now have two games in hand, while the victory moved Las Palmas up to 14th place on 15 points.
Las Palmas opened the scoring early in the second half when Sandro Ramirez scored a sublime goal against his former club but the home side equalised just after the hour when Raphinha fired a low, left-foot shot past ex-Barcelona keeper Jasper Cillessen.
Las Palmas were not deterred, however, and took the lead once again in the 67th minute as Wolverhampton Wanderers loanee Silva broke through the offside trap to latch onto a pass from Javi Munoz, outmuscled a defender and pulled the trigger.