Spanish football underlined its dominance of continental competition after Valencia, Athletic Bilbao and Atletico Madrid all advanced to the Europa League semi-finals, with Portuguese side Sporting joining them in the last four.
Valencia produced the night's most impressive display, overturning their one-goal first-leg deficit to AZ with some style, thanks to a 4-0 victory at the Mestalla.
France centre-back Adil Rami netted twice in two first-half minutes to put Los Che in control, and further goals from Jordi Alba and Pablo Hernandez put the tie to bed, as Unai Emery's side put last week's 2-1 defeat in Alkmaar firmly behind them.
Valencia will take on fellow La Liga outfit Atletico Madrid in the last four following their 2-1 victory in Hannover.
The Rojiblancos led 2-1 from the first leg and increased their advantage when Adrian pounced in the 63rd minute. Former Manchester United striker Mame Biram Diouf equalised for the hosts but in-form Falcao bagged late on to put the 2010 Europa League winners within two games of another final appearance.
Athletic Bilbao completed the trio of Spanish clubs reaching the semi-finals, after they twice came from behind to draw 2-2 with Schalke and preserve their lead from the impressive 4-2 first-leg victory over the Bundesliga high-fliers.
Europa League top scorer Klaas-Jan Huntelaar opened the scoring for Schalke with his 14th goal in 12 games in this season's competition, but a wonderful curling effort from Ibai Gomez - an early substitute for Mikel San Jose - levelled things up.
Raul restored Schalke's advantage with a fine strike of his own, but Markel Susaeta hit back for the hosts, who also have a Copa del Rey final against Barcelona to look forward to this month.
Sporting await Athletic in the semi-finals after they drew 1-1 with FC Metalist to progress 3-2 on aggregate.
Ricky van Wolfswinkel put Sporting ahead and though Jonathan Cristaldo hit back in Ukraine, the Portuguese side held on to give themselves a chance of emulating Braga and Porto, who both ensured a Primeira Liga presence in last season's final.