Aritz Aduriz’s late stunner was enough to earn Athletic Bilboa a hard fought 1-0 win against La Liga champions Barcelona, at San Mames.
The 38-year-old came off the bench to strike home a hammer blow with an incredible acrobatic scissor kick with just two minutes remaining, to down Ernesto Valverde’s side.
Both of Barca’s big summer signings went straight into the side. France World Cup winner Antoine Griezmann started alongside Luis Suarez and Ousmane Dembele in attack, while Frenkie de Jong lined up in midfield.
Messi was not in the squad because of calf injury, while Philippe Coutinho was not involved amid reports he is close to agreeing a loan move to Bayern Munich.
The £107m signing Griezmann failed to impress as Barca struggled to find a way past Unai Simon, and the stubborn Athletic defense.
Inaki Williams troubled the Barcelona defense all through the game, and was always a threat on the counter attack.
San Mames gave club legend Aduriz a huge roar when he replaced Williams in the second half. This will be his last season at the club.
The match-winning moment came when Aduriz met the cross from the right from Ander Capa, and struck superbly past Marc Andre ter Stegen.
What a way to start it and what a way to put Barcelona to the sword. This could top every great moment in the long career of Aduriz.
It capped a miserable night for Barca, who lost Luis Suarez to injury in the first half and hit the woodwork twice.