Pumas kept Liga MX's Copa Libertadores hopes alive with a 2-0 win versus Venezuelan side Deportivo Tachira to secure a 2-1 aggregate success and passage to the quarterfinals.
Trailing 1-0 from the first leg, Pumas' Eduardo Herrera headed home in the 13th minute to bring the hosts level on aggregate.
With the game seemingly headed to extra time and possibly penalties, Herrera found Ismael Sosa for the Mexican side's second goal to double the lead.
Minutes later, with Deportivo chasing a decisive away goal, Juan Carlos Mora was red carded and the visitors finished the match with 10 men.
Pumas could play River Plate in the next round, but the Argentine giants will need to pull back a two-goal deficit against Ecuador's Independiente del Valle on Wednesday in the two teams' last-16 second leg.
Alejandro Guerra scored twice as Colombia's Atletico Nacional beat Argentine side Huracan 4-2 on the night and on aggregate to advance.
The two teams drew 0-0 in the first leg in Argentina, but home advantage helped Reinaldo Rueda's team score four times to see off their visitors to the south.
Victor Ibarbo opened the scoring in the 24th minute from the penalty spot, but Huracan quickly levelled when Mauro Bogado found Cristian Espinoza in the centre of the box to even the score at 1-1.
Guerra scored his two goals after half-time and the hosts looked to have things in hand, but a Ramon Abila right-footed shot from the centre of the box made for anxious moments for the Colombian side late on.
El Verde put all fears of a Huracan fightback to rest when Jonathan Copete doubled his team's lead in injury time to secure passage to the last eight.