Aritz Aduriz consigned Barcelona to a 1-0 opening-day defeat at Athletic Bilbao with a spectacular overhead kick that belied his 38 years.
The veteran forward, who will retire at the end of the season, had only been on the pitch for a minute when he met Ander Capa’s cross with an acrobatic volley to net an 89th-minute winner at San Mames.
Defending champions Barca were without star man Lionel Messi, who is recovering from a calf injury, and were dealt a further blow when Luis Suarez was forced off with an apparent calf issue of his own late in the first half.
Suarez had squandered Barca’s best chance of the match, hitting the left-hand post after receiving a misplaced backpass in the penalty area, but it was Bilbao who looked most likely to make the breakthrough for much of the opening period, with Inaki Williams looking especially dangerous.
Bilbao sat deeper in the second half, inviting pressure from a Barca attack that had previously proved impotent.
However, Ernesto Valverde’s side, featuring debutants Antoine Griezmann and Frenkie De Jong, were unable to find a way through and Aduriz – an 88th-minute replacement for Williams – settled the encounter in sublime fashion.
The result ends a decade-long run of the Catalan giants winning their opening game of the season.
Barca were sloppy early on and a loose Ousmane Dembele pass opened the door for Wiliams to test the alertness of Marc-Andre Ter Stegen seven minutes into the new season.
Williams, who signed a nine-year contract this week, unleashed a fierce strike from 25 yards out but was denied by an accomplished diving save from the German goalkeeper.
Ter Stegen was called into action again eight minutes later, getting down well to keep out another Williams effort after the forward breached the Barca defence.
The visitors were having trouble finding their stride, with Griezmann – stationed wide on the left of a front three – struggling to make an impact.
But Barca were almost gifted the lead when a poor Unai Lopez back pass found Suarez in space in the centre of the penalty area, only for the former Liverpool forward to strike the woodwork with his shot on the turn.
Suarez appeared to pick up a calf problem in the act of shooting and was replaced by Rafinha eight minutes from half-time, with Valverde taking the opportunity to shift Griezmann into a more central role.
Rafinha almost made an instant impact, his curling shot from the edge of the box superbly tipped onto the crossbar by Unai Simon, and he sent an effort between the legs of the goalkeeper and just wide early in the second period.
With the hosts taking a cautious approach after the interval, Barca dominated possession and half-time substitute Ivan Rakitic blazed an effort over from a promising position in the 70th minute.
The match appeared destined for a goalless draw, however, until Aduriz kicked off his farewell campaign with a stunning volley that will take some beating in LaLiga this season.