Lionel Messi kept his nerve from the penalty spot to give Barcelona a 1-0 win over Real Sociedad in La Liga on Saturday and return his side to the top of the table.
Barca's all-time top scorer calmly chipped the ball into the net in the 81st minute after Sociedad defender Robin Le Normand had been penalised following a VAR review for hitting the ball with his arm as he contested a cross.
The penalty was awarded at a time when Barca were struggling to cope with Sociedad's flowing counterattacks, with the Basques missing several chances to take the lead at the Camp Nou in a bold second-half display.
Sociedad's frustration at conceding the penalty was heightened when their former player Antoine Griezmann appeared to push over defender Nacho Monreal in the area but no foul was awarded.
Barca looked to have scored a second goal deep in injury time when Jordi Alba slotted in a cross from substitute Ansu Fati but another VAR review determined that the teenage forward had been narrowly offside when he received the ball from Messi.
The victory took Barca back to the top of the standings on 58 points after 27 games although Real Madrid, on 56, can restore their place at the league summit by beating Real Betis on Sunday.
"We won the game with the narrowest of margins but it keeps our hopes of winning the title alive," said Barca defender Gerard Pique, who also defended the decision to award his side the crucial penalty.
"We have seen several similar situations punished with a penalty recently so as soon as I saw it I thought it was handball," he added.
Sociedad midfielder Mikel Merino was encouraged by his side's performance but was frustrated by the result.
"We feel a mixture of feelings as we played really good football, had chances and dominated phases of the game but we lost due to a handball which was very questionable," he said.
Barca were under extra pressure to win after losing last week's 'Clasico' 2-0 away to Madrid and surrendering top spot to their rivals, and were up against a Sociedad side on a run of six straight victories in all competitions.
Sociedad travelled to Barcelona in jubilant mood after booking their place in the Copa del Rey final for the first time in 32 years by seeing off Mirandes on Wednesday and coach Imanol Alguacil made a series of changes to his starting line-up.
Barca's latest arrival Martin Braithwaite made his first start for the home side and was their most lively player in the first half, combining well with Messi and twice forcing saves from visiting keeper Alex Remiro.
Messi missed the target with his only effort before the interval and also looked rusty in the second half until he placed the ball on the spot and coolly dispatched it into the net.