Antoine Griezmann and Rodrigo Riquelme's extra-time strikes earned Atletico Madrid a 4-2 win over rivals Real Madrid and passage to the Copa del Rey quarterfinals on Thursday.
Earlier Barcelona secured an unconvincing 3-1 win at third-tier Unionistas de Salamanca to scrape through their last-16 tie.
Atletico edged an entertaining battle at the Rojiblancos' Metropolitano stadium, the second of three Madrid derbies in under a month, to inflict Los Blancos' second defeat of the season in all competitions.
Madrid twice pegged back Atletico to take the game to extra-time, with Jan Oblak's own goal cancelling out Samuel Lino's opener, and Joselu netting late on after Morata had put the hosts in front again.
In extra-time Griezmann broke down the right and finished with aplomb and Riquelme struck at the death to settle the game and avenge Atletico's 5-3 defeat by Madrid in the Spanish Super Cup semifinal last week.
Defeat snapped Madrid's 21-match unbeaten run.
"I don't think (Atletico have the measure of us), because we beat them a few days ago," Real Madrid coach Carlo Ancelotti told reporters.
"We played a complete game, even, hard-fought, against a strong rival."
Once again, the match flowed end-to-end. Jude Bellingham hit the crossbar for Madrid before Atletico took the lead when Lino finished from close range.
However the Spanish Super Cup winners levelled before the break when Luka Modric's crossed free-kick drew Oblak out of his goal.
The Slovenian, leaping to reach the ball but unable to grab it, ended up getting the final touch as it span into his own net.
Real Madrid winger Vinicius Junior celebrated the equaliser more fiercely than anyone, with no love lost between the Brazilian and Atletico's supporters.
The home
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