Barcelona's hopes of achieving a second successive double were thwarted as Valencia marked their centenary season in style with a 2-1 victory in the final of the Copa del Rey.
The Spanish champions were hot favourites to lift the trophy for a fifth successive year having sealed the La Liga crown with resounding ease and finishing 26 points above Valencia, who finished fourth.
However Barca found themselves 2-0 down at the break thanks to goals from Kevin Gameiro (21') and Rodrigo (33') at Seville's Benito Villamarin.
Lionel Messi had already admitted the prospect of winning double in his first 'tainted' season as captain wouldn't take away the pain he still felt from their Champions League exit at the hands of Liverpool, but now he was facing more disappointment.
Messi duly pulled one back in the 73rd minute but the equaliser never came and Valencia were able to celebrate winning the trophy for the eighth time in their history and the first since 2008.
Barca were aiming for an unprecedented fifth-successive Copa del Rey success, and seventh in 11 years, but never recovered from going behind.
Having comfortably won another domestic title, they put all their efforts into winning the Champions League and their failure to even reach the final after a 3-0 first-leg lead over Jurgen Klopp's side appears to have weighed heavy on the players.
On the eve of the game Messi said: "It was a really big blow which we received at Anfield. It was tough to get back up. It was one of the worst experiences in my career."
Little did he realise there would be more pain to follow in Real Betis' Estadio Benito Villamarin in Seville, where temperatures at the 9pm local kick-off time were still around 30 degrees Celsius.
Valencia had just 23 per cent possession in the game but that was not the statistic which mattered, especially as, although their opponents registered 26 attempts, only six were on target in 90 minutes.
The fact Barca were missing Luis Suarez, who failed to recover from a knee operation in time, was a significant factor.
Gameiro took his tally to four goals in as many matches in the 21st minute, firing into the top corner after Ezequiel Garay cleverly cut back the ball.
Barcelona were reeling further when Carlos Soler broke down the right, outsprinting Jordi Alba, to tee up Rodrigo to plant a header past Jasper Cillessen.
Valencia's two-goal half-time lead was the first against the 30-time winners in the final since Real Madrid in 1974.
Ernesto Valderde immediately changed tactics for the second half, sending on winger Malcom for defender Nelson Semedo and Arturo Vidal for fellow midfielder Arthur.
However, Valencia were first to threaten again with Rodrigo having a shot saved before, 11 minutes in, Messi hit the crossbar after a one-two with Malcom.
It was a warning not heeded as Clement Lenglet's header hit the post to allow Messi to tidy up and become the first player to score in six different Copa del Rey finals.
Valencia had 17 minutes to hang on and - despite everything thrown at them, including centre-back Gerard Pique playing up front - they held on to lift their first Copa del Rey in 11 years.