Coach Ernesto Valverde said Athletic Bilbao's fans deserved Monday's result as the club ended a 31-year drought for a trophy by claiming the Spanish Super Cup on Monday.
The Basque club last won silverware in 1984, when they defeated Barcelona 1-0 in the Copa del Rey final to complete a league and cup double.
But there were to be no further trophies until they managed a 1-1 at the Camp Nou to defeat Barcelona 5-1 on aggregate.
Athletic withstood constant pressure from the first kick of the game and limited the European champions to Lionel Messi's lone goal.
"The first half was very hard because they are very good and pressed a lot," Ernesto said after the game.
"In the second half we were good and we reached our objective. From the outside you might think we didn't feel it too badly but yes, when they scored, we were shaken.
"We've finally achieved the trophy that these people deserve."
Aritz Aduriz scored his fourth goal in the two-game competition, following up his first-leg half trick to equalise on the night.
"If you wrote a script it would be impossible for it to go this well," the striker said.
"Winning a trophy is the greatest thing that can happen and even more so against Barcelona.
"It's incredibly satisfying to win a trophy with Athletic. It's the best we can hope for. We have something special that makes us strong. It's amazing.
"The happiest day of my life was the birth of my daughter but apart from that, today is the happiest day."
Midfielder Carlos Gurpegui called the victory a "dream come true."
hailed Athletic Bilbao's Supercopa de Espana win as 'a dream come true' after Barcelona were soundly beaten.
"It's amazing. All my life it's been my dream to get a trophy. It's a dream come true. The strength to win this trophy at Barcelona means so much to us," he said, Marca reports.
"If any club in the world deserves this, it's Athletic."