Getafe's Mauro Arambarri scored a last-gasp quickfire double to upset 10-man Atletico Madrid 2-1 on Sunday as Diego Simeone's side missed a golden opportunity to move top of LaLiga.
With a game in hand, Barcelona lead with 57 points, one ahead Atletico and three clear third-placed Real Madrid who host Rayo Vallecano later on Sunday.
Atletico's Alexander Sorloth came off the bench to convert a penalty in the 75th minute after a long VAR review spotted a handball which left the home team fuming.
Seconds after Guillermo Cuadra flashed a straight red to Atletico's Angel Correa for a studs-up tackle in the 88th minute, however, Arambarri stroked home a rebound from close-range and two minutes into added time he deflected Diego Rico's shot past goalkeeper Jan Oblak and into the net.
"After we scored the goal we knew they were going to go up and even so we lost the game at the end," Atletico midfielder Pablo Barrios told DAZN.
"We were doing OK but after (Correa's) red card, with one less player, it got away from us... Until we scored the goal we had the game under control. With the sending-off we didn't know how to control the result."
Atletico will face old rivals Real Madrid in the second leg of their Champions League round of 16 tie on Wednesday before hosting Barca in LaLiga on Sunday.
Simeone decided not to rest any key players as a win at Getafe would put Atletico top of the standings after Barcelona's game against Osasuna on Saturday was postponed due to the sudden death of their team doctor.
Despite dominating possession, however, Atletico were toothless up front as LaLiga's top two defences clashed, cancelling each other out in a dour game, with both sides struggling to find space.
Atletico had no shots on target until the referee awarded them the penalty for a handball by Getafe defender Omar Alderete which Sorloth netted with a low strike to the goalkeeper's left.
Correa's nasty challenge on Djene left Atletico a man down, however, and Getafe pushed forward and were rewarded with Arambarri's double strike.