Malaga booked their place with the elite last eight in Europe after Manuel Pellegrini’s men overcame a one-goal first-leg deficit to beat 10-man Porto at La Rosaleda.
Isco’s wonderful opener minutes before the break gave the home side the lead to cancel out Joao Moutinho’s first-leg goal before substitute Roque Santa Cruz scored just four minutes after coming on to seal a famous win.
With a four-year European ban hanging over them, this year’s competition is all the more important for the Spaniards, who ramped up the pressure after Steven Defour saw red four minutes into the second half.
After a slow start, Julio Baptista headed tamely over from an Isco free-kick in the 11th minute. The first 30 minutes were dominated by bookings with neither side holding back.
Porto’s Nicolas Otamendi was the first to see yellow after 17 minutes, before Martin Demichelis, Defour, Alex Sandro and Jesus Gamez all joined him in the book.
Joaquin shot over just after the half-hour mark before Vitorino Antunes forced a decent save out of Porto stopper Helton.
Malaga finally got their goal their pressure deserved after 42 minutes, Isco curling a wonderful effort over Helton and into the top corner to put his side level on aggregate.
Just four minutes into the second period the visitors were reduced to 10 men when Defour received a second yellow for a petulant trip on Joaquin.
Substitute Santa Cruz put his side ahead after outjumping Otamendi from an Isco corner to plant his header past a diving Helton for the crucial winner.