All but one of the ties seem to be open for surprises, which is why we encourage you to keep track of these games with our guide.

The 2021 edition of the Copa Libertadores has entered its definitive stage, and after the end results of the first legs in the Quarter-finals, there are some of these teams that could very well start making plans for the semi-final stage.

Brazilian teams have continued to dominate in the competition, since none of them (including those who played against each other) will have to come from behind if they want to make the next round. On the contrary, teams from other countries will need to play their best games if they don't want to see a vast majority of Brazilian teams in the semis.

This week's activity will be divided between Tuesday and Thursday, with Wednesday being packed with two games. Here is how the games will be played in chronological order and the first leg result included in the parentheses.

Palmeiras vs Sao Paulo (First leg result:1-1)

The defending champions get to this game with all to play for thanks to a late goal by Patrick de Paula. Now, a goalless could be enough for them to seal their spot in the next round, but Hernán Crespo's team has shown previously just how effective they can be when they play at home.

Flamengo vs Olimpia (4-1 para Flamengo en la ida)

The 2019 Copa Libertadores winners have everything in their favor to claim the ticket to the semi-finals, since only a catastrophe would see them concede four times at Maracaná Stadium. If that was not enough reason to believe in their chances, Renato Portaluppi's men will have Gabriel Barbosa in fine form for this game, which means that Olimpia will have to come up with a historic display to turn things around.

Atlético Mineiro vs River Plate (1-0 para Mineiro en la ida)

The team with the best record in the Copa Libertadores claimed a huge away win against Marcelo Gallardo's men. Now, Cuca's team will have to show the same kind of defensive prowess as they have done in previous KO stage games, where they are yet to concede against two Argentine powerhouses such as Boca and River. If they are unable to do so, then River Plate could find an opening to shock them at the Mineirao in what could be the most interesting tie to watch in the last eight stage.

Barcelona vs Fluminense (2-2 en el juego de ida)

The team from Guayaquil came truly close to claiming a massive win, but Fred's penalty ended their hopes of a victory in the first leg. Now, the home-field advantage will be Barcelona's, but the main problem for them will be that "Flu" are yet to lose an away game in this Copa Libertadores edition, and if they keep that streak going, they will have a legitimate shot at claiming a spot in the final four.

Don't miss a beat of these games in the Copa Libertadores Quarter-finals by clicking on the link of the game you are eager to watch. Once there, you will find every detail you need to keep track of the matches.