Atletico Nacional, Boca Juniors, Corinthians and Velez Sarsfield are just some of the teams who can clinch places in the last 16 of the Copa Libertadores 2012 over the next three days. With 11 games on the card and a generous sprinkling of qualification slots on offer, the permutations are endless, as reveals.

Game of the week
Olimpia (PAR) - Emelec (ECU)
Group 2 – Thursday 12 April, 19:30 (local time), Estadio Defensores del Chaco

El Decano can mark their return to the Libertadores after an eight-year absence with progress to the knockout phase if they prevail in this winner-takes-all meeting. Lying second, three points adrift of leaders Lanus and one point ahead of Emelec, the Paraguayans are nevertheless licking their wounds after the 6-0 thrashing they suffered at the hands of the Argentinians last week. In contrast, their Ecuadorian opponents will be full of confidence after stunning Fla 3-2 to give themselves control of their own destiny. A draw will prove fatal for both sides if bottom-placed Flamengo beat Lanus. Any other outcome will see Fla become the first Brazilian side to fall at this stage of the competition since Internacional in 2007.

Group 2 is not the only section where a qualification slot is up for grabs this week. Second in Group 8 and the competition’s highest scorers with 12 goals, Atletico Nacional will seal their place in the last 16 if they earn a draw at home to the already eliminated Penarol.

Over in Group 4, Boca Juniors will advance without kicking a ball if Zamora overcome third-placed Arsenal in Venezuela on Tuesday. Should Arsenal win, Los Xeneizes will have to beat leaders Fluminense in Rio de Janeiro 24 hours later if they are to go through with a game to spare, though the Brazilians will no doubt be aiming for their fifth win in as many matches to seal first place.

The winner of Tuesday’s meeting between Union Espanola and Bolivar in Santiago will advance from Group 3, while Group 7 leaders Velez Sarsfield will book their safe passage if they take a point from their trip to Guadalajara, with Defensor Sporting sure to advance from the same pool if they win at Deportivo Quito.

Finally in Group 6, Corinthians have the chance to progress and take Cruz Azul with them if they collect three points on their trip to Nacional of Paraguay, who are battling to keep their qualification hopes alive.

Player to watch
Leandro Castan (Corinthians)
A lot has been said about Corinthians’ attacking options in the build-up to their meeting with Nacional, yet the 25-year-old defender could well have just an important part to play as the men up front. Tall, strong and mobile, Castan has become a mainstay of the Sao Paulo giants' rearguard this season and is a big reason why they have conceded just one goal in the Libertadores so far, the best record in the competition.

Did you know?
Following the elimination of Nacional and Penarol, Defensor Sporting are the only Uruguayan side still in with a chance of reaching the next round. Los Violetas, who lie second in Group 7, are aiming for a repeat of their last appearance in the competition in 2009, when they reached the quarter-finals before being knocked out by eventual champions Estudiantes.

What they said
Dario Cvitanich, Boca Juniors forward:
“We’ve got no score to settle with Fluminense, just a great chance to put ourselves in a position to qualify. We know that we’ve still got a game to come after this one and that anything can happen. It’s all in our hands and we’ll be going all out for the win."

This week's fixtures

Union Espanola (CHI) - Bolivar (BOL)
Zamora (VEN) - Arsenal (ARG)
Deportivo Quito (ECU) - Defensor Sporting (URU)
Atletico Nacional (COL) - Penarol (URU)

Fluminense (BRA) - Boca Juniors (ARG)
Nacional (PAR) - Corinthians (BRA)
Guadalajara (MEX) - Velez Sarsfield (ARG)

Flamengo (BRA) - Lanus (ARG)
Olimpia (PAR) - Emelec (ECU)
Nacional (URU) - Vasco da Gama (BRA)
Alianza Lima (PER) - Libertad (PAR)