Athletic Club earned a 3-2 win over Barcelona after extra time thanks to an Inaki Williams strike to lift the Supercopa de España trophy on Sunday night.
La Blaugrana saw most of the ball in the early stages of the match but found it very difficult to pierce through Bilbao's rigid and organised lines. That said, Marc-Andre ter Stegen was forced into a great save from Ander Capa's strike on 25 minutes.
However, it was Barcelona who found the first goal as the ball broke Antoine Griezmann's way in the box, before the Frenchman clinically slotted home. Bilbao, however, went straight up the field from kick off and replied instantly when Williams' cross found Oscar de Marcos, who finished calmly at the back post past an onrushing Ter Stegen to put the sides on level terms at the break.
Bilbao had a goal disallowed ten minutes into the second half when Iker Munain's free kick found Raul Garcia in an offside position. The second half continued at a slow pace until the 77th minute when Barcelona found a second through Griezmann, who calmly netted after good work down the left between Ousmane Dembele and Jordi Alba.
La Blaugrana couldn't see the game out, however, and conceded a disappointing 90th minute equaliser as a set piece found Asier Villalibre, who finished from three yards out to take the match to extra time.
It didn't take long for the Basque side to take the lead for the first time as Williams produced a bit of magic to find the top corner with a spectacular strike for the game's deciding strike.
Despite knocking on Athletic's door throughout extra time, Barcelona couldn't find a reply to Williams' strike. Matters were made worse when Lionel Messi received a red card for an off-the-ball incident with Villalibre, ending La Blaugrana's hopes and allowing Bilbao to see out a 3-2 victory.
Now, to the Barcelona ratings.
1. Goalkeeper & Defenders
Marc-Andre ter Stegen (GK) - 6/10 - Despite a couple of good saves, he couldn't provide the same heroics as the semi final, and really wasn't helped out by his defenders.
Sergino Dest (RB) - 5/10 - Was forced off at half time through injury. He wasn't missed, however, having failed to make an offensive impact in the first 45 - no crosses or key passes.
Ronald Araujo (CB) - 7/10 - Another assured performance at the back. The Uruguayan made a crucial tackle as Williams looked through on goal at 1-1, as well as five clearances to bail his side out of danger.
Clement Lenglet (CB) - 6/10 - Won the ball three times for his side, but did have to rely on Araujo's pace on several occasions.
Jordi Alba (LB) - 3/10 - Provided a good assist for his side's second, but was at fault for both Bilbao equalisers in normal time with truly terrible defending - one to forget, to say the least.
Sergio Busquets (DM) - 7/10 - Made 124 touches as he linked defence and the players in front of him, while also winning the ball back five times. Another solid showing before being taken off.
Frenkie de Jong (CM) - 7/10 - A poor performance in the first 45 but normality resumed afterwards as he drove forward, provided options in the final third and distributed the ball quickly and efficiently, eventually achieving a 96% pass accuracy.
Pedri (CM) - 5/10 - Was barely noticeable in the first half and really struggled in the second as Bilbao's physicality afforded him no time or space on the ball.
Ousmane Dembele (RW) - 5/10 - The winger was crucial in the build up to the second Barcelona goal but for the most part found no end product in his game as he inexplicably favoured cutting into a sea of bodies every time he had the ball.
Lionel Messi (ST) - 5/10 - One to forget for Messi. Failed to make an impact after playing a vital role in the opener, being marshalled to perfection when he dropped deep. His torrid outing was brought to an end when he got sent off in the 119th minute.
Antoine Griezmann (LW) - 7/10 - Another good performance from the Frenchman as he scored his third and fourth goals in three matches for La Blaugrana. The forward had a difficult chance in the 110th minute but couldn't volley home in the box to draw the sides level.
Oscar Mingueza (RB) - 6/10 - The 21-year old provided more attacking impetus down the right in place of Dest but still struggled defensively, making only one tackle.
Miralem Pjanic (CM) - 5/10
Martin Braithwaite (RW) - 6/10
Riqui Puig (CM) - 7/10 - Showcased a wonderful range of passing and technical ability. La Blaugrana looked more threatening after he came on, completing dribbles and finishing with a 96% pass accuracy.
Trincao (ST) - 5/10