10-man Boca through to Copa Libertadores final
Atletico Nacional and Boca Juniors prevailed against Rosario Central and Nacional respectively to setup a final-four showdown.
Boca prevailed 4-3 in a penalty shootout against Uruguayan side Nacional, but the Argentinian champion did it the hard way after Christian Pavon received a second yellow card for taking off his shit in a goal celebration.
Penalties were required after the quarterfinal tie in Buenos Aires was deadlocked at 2-2 on aggregate after Friday's 1-1 stalemate.
Coming off a 1-1 first-leg draw, Nacional drew first blood away from home via Daniel Diaz's own goal in the 21st minute.
Pushing forward in search of an equalizer, Boca was finally rewarded with 17 minutes remaining but it came at a cost.
Cristian Pavon leveled proceedings but the striker was shown a second yellow card for taking off his shirt in celebration, just six minutes after picking up his firs yellow though Boca went on to win after Nacional missed its final three spot kicks.
Meanwhile, Atletico Nacional overcame Rosario Central 3-1 in a heated finish on Thursday to book a spot in the semifinal of the Copa Libertadores.
Second-half substitute Orlando Berrio scored in the fifth minute of injury time to seal Nacional's spot in the final four as a 3-2 winner on aggregate.
The quarterfinal second leg fixture in Colombia ended with four red cards shown in stoppage time, three of those to Rosario players - Esteban Burgos, Damian Musto and Giovani Lo Celso.
Leading 1-0 after the first leg, Argentina's Rosario extended its advantage early in the return clash thanks to Marco Ruben's ninth-minute penalty.
But it was one-way traffic from that point as Macnelly Torres equalised in first-half stoppage time, and Alejandro Guerra put Nacional 2-1 up on the night just five minutes after the break.
With Rosario throwing numbers forward, Berrio came off the bench and secured a third semifinal appearance for Nacional before he was sent off.
Awaiting 1989 winner Nacional in the semifinals is six-time champion Boca Juniors.