The reigning champion was on course for a third consecutive league success when Jules Kounde gave it the lead in first-half added time at Estadio El Sadar.

Chimy Avila levelled for the hosts in the 76th minute, only for Robert Lewandowski to convert a penalty he had won which earned Osasuna defender Alejandro Catena a red card with five minutes remaining.

The three points means Xavi’s side joins second-placed Girona on 10 points from four matches in Spain’s top flight.

Barcelona almost took an early lead when Frenkie De Jong hit the bar and Lewandowski was unable to convert the rebound.

Lamine Yamal was next to threaten for the visitors in the 10th minute but his effort was repelled by Osasuna goalkeeper Aitor Fernandez.

Osasuna’s Jose Arnaiz drew a sharp save from Marc-Andre ter Stegen in the 23rd minute and eight minutes later the home side threatened again, with the Barca goalkeeper keeping out an effort from Aimar Oroz.

However, Barcelona was ahead shortly before the interval through France international Kounde, who headed in an Ilkay Gundogan corner from eight yards. It was the 24-year-old defender’s first goal for Barcelona since its derby win at Espanyol on 15 May (AEST).

Joao Cancelo came on as a substitute for his debut just before the hour mark and 11 minutes later he almost set up a second goal for the visitors.

The on-loan Manchester City full-back found Lewandowski at the far post but Fernandez was able to block his close-range effort.

However, the visitors levelled soon after with a stunning left-footed strike from Avila.

The Argentinian forward made space for himself on the edge of the Barca box before unleashing a 20-yard curling effort which beat Ter Stegen and found the net via a post.

However, the hosts’ hopes of taking a point ended with 10 minutes remaining when Catena dragged back Lewandowski inside the Osasuna penalty area.

Referee Miguel Ortiz consulted VAR before dismissing the centre-back and, after a delay of nearly five minutes following the original offence, the Pole kept his nerve to send Fernandez the wrong way from the spot.

Osasuna had appeals for a penalty of their own turned down in the third minute of stoppage-time when Ante Budimir went down under pressure from fellow substitute Inigo Martinez.

However, the game was not to get a second spot-kick and Barca saw out a further eight minutes to secure the three points.