Real Betis ended third division Gramenet's heroic King's Cup run on Wednesday with a thrilling 4-3 home win to book their place in the semi-finals 6-5 on aggregate.
Betis looked on course for an easy victory after quick-fire strikes from Fernando and David Rivas put them 2-0 up but giant-killers Gramenet scored three second-half goals to set up a nail-biting finale.
Earlier, Osasuna reached the semis for the second time in three seasons as a 3-1 home win allowed them to turn round a first-leg deficit and seal a 4-3 aggregate victory over Sevilla.
Midfielder Inaki Munoz
looked to have wrapped up a comfortable win when he put the finishing touch to a lightning counter-attack to make it 3-0 in the 90th minute, but an injury-time strike by Sevilla substitute Ariza Makukula made for another exciting finish.
Atletico Madrid ground out a 0-0 draw at Numancia in a first leg match that was postponed after the original fixture was called off because of a frozen pitch.
In the other second-leg match, 23-times champions Athletic Bilbao travel to Valladolid on Thursday holding a 3-2 advantage after the second division side gave the Basque outfit a rough ride in the first leg.
Osasuna cancelled out Sevilla's first-leg advantage 25 minutes into the game at El Sadar when midfielder Valdo
headed home after great work by fullback Rafael Clavero on the left.
The Navarrans extended their lead midway through the second half when centre-back Carlos Cuellar ghosted in at the far post to head home from close range after a free kick and midfielder Inaki Mnoz made it 3-0 in the final minute of normal time when he put the finishing touch to a slick counter-attack.
Sevilla striker Ariza Makukula pulled a goal back in stoppage time, but Javier Aguirre's side held on safely for the win.
Trailing 2-0 at the break, midfielder Miki Albert put Gramenet back in their tie against Betis when he turned the ball in from close range after Aaron Bueno
had cut a fine pass across the face of the goal.
The home side restored their advantage just before the hour was up, in-form Br azil
ian striker Ricardo Oliveira volleying into the top corner after an attempted clearance dropped into his path.
Gramenet were not going to give up without a fight, however, and substitute Ruben
Blaya kept their hopes alive when he poked home from a metre out after Betis keeper Pedro Contreras had spilled a free kick.
The see-saw battle continued when free kick expert Marcos Assuncao put Betis 4-2 up with a trademark strike from the edge of the area, but Bueno
set up a thrilling finale when he toe-poked in three minutes from time.