Alaves scored with the last kick of the game to beat Real Madrid 1-0 and condemn Los Blancos to their worst goal drought for 33 years.
A cagey affair was decided at the death by Manu Garcia as Madrid’s run without a goal exceeded six hours and run without a win extended to four games, while the stalwart’s header earned Alaves their first home victory over the capital giants in La Liga since 1931.
Gareth Bale and Karim Benzema partnered each other in Los Blancos' attack, with Dani Ceballos taking the No 10 role over the injured Isco, but Mariano Diaz and Vinicius were only substitutes.
Elsewhere, Alvaro Odriozola and Nacho Fernandez filled each full-back berth as Dani Carvajal and Marcelo were sidelined.
Alaves, meanwhile, had yet to lose at home this season and could move joint-top of La Liga if they beat Madrid and other results went their way.
Madrid tested youth product Fernando Pacheco early on with a flurry of snapshots, but none of them came closer than Karim Benzema’s header, which Victor Laguardia hacked away from goal.
However, at the other end Raphael Varane threw himself in front of Ibai Gomez before the winger could turn in Jonathan Calleri’s chipped cross from the byline.
Ruben Duarte stung Courtois’ palms with a half-volley, but Los Merengues were unlucky not to have been awarded a penalty when Guillermo Maripan seemed to take out Alvaro Odriozola in the box.
It got worse for Madrid when Gareth Bale trudged off with an apparent injury, paving the way for Brazilian teen sensation Vinicius Jr to make a late cameo.
Yet Julen Lopetegui’s side still toiled, even with Mariano also on the pitch, and Manu pounced on a rebound from a corner in the fifth minute of stoppage time to send Mendizorroza into raptures.
Alaves 1-0 Real Madrid
Alaves: Pacheco; Ximo, Laguardia, Maripan, Ruben Duarte; Brasanac, Pina, Wakaso (Manu 74); Ibai (Sobrino 67), Calleri, Jony
Real Madrid: Courtois; Odriozola, Varane, Ramos, Nacho; Modric, Casemiro (Asensio 62), Kroos; Ceballos; Bale (Vinicius 80), Benzema (Mariano 46)
Referee: Jaime Latre