Raul Garcia scored twice as Athletic Bilbao secured a rare 2-1 win over holders Real Madrid to set up a Supercopa de Espana final against Barcelona.
Athletic had won only one of their previous 22 matches against the LaLiga champions but beat them for the first time since March 2015 at La Rosaleda on Thursday to hand Marcelino his first victory.
Raul Garcia was set up by Dani Garcia for the opening goal and struck again from the penalty spot to stun Madrid in the first half.
Karim Benzema reduced the deficit after Marco Asensio struck the woodwork twice, but Bilbao held on to end Madrid's nine-match unbeaten run and ensure they will do battle with Barca for the trophy at Estadio de La Cartuja on Sunday.
Athletic did not allow Madrid to settle and they were in front in the 18th minute when Dani Garcia picked up a sloppy pass from Lucas Vazquez and threaded an incisive ball through for the unmarked Raul Garcia to slot beyond Thibaut Courtois.
Having flashed a venomous shot wide as the Basque side continued to press Los Blancos high up the pitch, the experienced midfielder was on target again seven minutes from time.
Another lapse from Vazquez proved to be costly, the defender bundling over Inigo Martinez and Raul Garcia sending Courtois the wrong way with an expertly taken spot-kick seven minutes before the break.
Nacho Fernandez replaced Raphael Varane at half-time and Iker Muniain ought to have put Athletic three goals to the good when he nodded Oscar De Marcos' cross wide of the near post from close range.
Asensio twice came close to halving the deficit in quick succession, rattling the near post from close range before striking the crossbar with a rasping long-range drive.
Benzema pulled one back when he was ruled onside following a VAR check after the flagged was initially raised with 17 minutes remaining.
France striker Benzema had the ball in the back of the net again but this time he was ruled to be offside after Courtois denied Asier Villalibre and Sergio Ramos headed just wide, then Athletic breathed a huge sigh of relief when the VAR verdict was no penalty for Madrid for a possible handball right at the death.
What does it mean? Promising start for new boss Marcelino
Marcelino suffered a 3-2 defeat in his first game in charge against Barca last Wednesday and the new head coach will have a swift opportunity to gain revenge.
Athletic were excellent in the first half and although they tired somewhat after the break with Madrid applying the pressure, they were able to end a run of 11 games without beating Los Blancos.
Madrid had 21 shots to Athletic's eight, but only six of those were on target and Benzema's 13th goal of the season was in vain.
Evergreen Raul Garcia punishes Madrid
Raul Garcia might be heading for the twilight of his career at the age of 34, but he clearly still has plenty to offer.
As well as finishing clinically, he won six aerials duels, had 41 touches and was a thorn in the side of the Madrid defence, proving to be Athletic's match-winner.
Vazquez lapses costly
Vazquez endured a first-half nightmare in Malaga, with his stray passing giving Dani Garcia an opportunity to expose a gaping hole between Varane and Sergio Ramos, which Raul Garcia capitalised on to open the scoring.
The full-back was also at fault for the second goal, pulling down Inigo Martinez blatantly to gift a grateful Raul Garcia the chance to double his tally from 12 yards.
Key Opta Facts
- Athletic Bilbao will play their fourth Supercopa de Espana final, all of them against Barcelona.
- Zinedine Zidane has lost his first match against Athletic (P10, W6, D3, L1) and his first Supercopa match (P5, W3 D1 L1).
- Thibaut Courtois has conceded a goal from 16 of the 18 penalties faced as Real Madrid goalkeeper in all competitions, including the last nine in a row.
- No LaLiga team has hit the woodwork more often this season in all competitions than Real Madrid (20), six more than the next highest in that list (Villarreal, 14).
- Marcelino has beaten Real Madrid in back-to-back games for the first time in all competitions (W4, D3, L10). His four wins against Los Blancos have been with four different teams: Recreativo de Huelva, Villarreal, Valencia and Athletic.
Athletic go in search of glory in Seville this weekend, while Madrid will be licking their wounds before returning to action at Alcoyano in the Copa del Rey round of 32 next Wednesday.