It's been over a year and a half since Argentina and Uruguay met each other on the pitch. The winner takes all at this Clasico Rioplatense
South American powerhouses reacted on time for the last game of the group stage and secured their place among America's fittest eight.

Despite their overwhelming attack, Mano Menezes' Canarinha granted far too much space to their rival in the box. Alexandre Pato believes "A new Copa America starts now", but I think the Brazilians have a lot of work to do if they're meant to reach the finals.

I don't think there's any doubt Sergio Aguero should be part of Argentina's starting eleven for the derby against Uruguay. I believe Sergio Batista managed to build a new identity in the last game while sticking to the same scheme, with Fernando Gago and Angel Di Maria controlling the flow of the ball and Aguero and Gonzalo Higuain as alternatives to Lionel Messi in the attack.

Barcelona's star played his best game with La Albiceleste this year as the main engine of the attack, unlike his fellow Blaugrana partner Gabriel Milito, who has not yet been able to recover his form. Having played only 10 games for Barcelona this season, Milito is not the only weakness in the Argentinian defense.

The Brazilians may have avoided Argentina, Uruguay and Colombia at least until the final game, but will the confidence they've gained against Ecuador be enough to help them against Paraguay? Let's not forget Los Guaranies were one minute away from defeating Brazil in the second game, if it wasn't for Fred's equalizer on injury time.

Venezuela and Peru earned their place in the quarters against all odds, and they look forward to demonstrate they have not claimed their ticket just by chance. Los Vinotintos have several aces up their sleeve, as they've showed against Paraguay with their goalkeeper Renny Vega connecting a powerful header inside Guarani's box.

There's more in Peru than Paolo Guerrero, though the contribution of Hamburgo's striker is of course fundamental. Fiorentina's Juan Vargas understands the inner functioning of his scheme and has played a vital role in the group stage.

Peru must find a way to be aggressive without compromising their defense. Radamel Falcao is one of those players that knows how to take advantage of situations like that, can Peru reach the semi-finals at Colombia's expense?

I believe Chile is one of the main candidates to lift this year's title, mainly thanks to their coherence and organic behavior. Venezuela came back from a 3-1 partial defeat against Paraguay, and the confidence they've gained may provide the additional strength they need to defeat La Roja.

Brazil and Argentina are always favorites to reach the semi-finals. I believe Alexis Sanchez and Radamel Falcao are likely to lead Chile and Colombia to the next round.

I'm also positive that the rest of the contenders will grow as a serious rival upon defeating a candidate, and let's not forget Uruguay has won just as many American titles as Argentina.