The group stage is over, and the chaff has been separated from the wheat (except for Greece). There is no more playing for a point or counting on goal difference; every team will be playing for its tournament life in every match from here on out. The knockout rounds begin today with the hosts taking on a dangerous challenger and two teams with solid defenses who will be looking for a moment of magic.
Brazil (winner group A) v. Chile (runner-up group B)
The pressure here would rest squarely on Brazil, except for the fact that we are now in the single-elimination phase of a tournament that happens once every four years, so the pressure is kind of on everyone. Still the Brazilians are both the host (playing in front of their own soccer-crazed fans kind of cuts both ways) and the favorites, which might cause some teams to tighten up. It must be said that they haven't been wholly impressive so far, needing an own goal and a questionable penalty to take down Croatia and drawing against Mexico before demolishing Cameroon. The team's attacking creativity has flown through Neymar, and anyone capable of holding him in check could derail the hosts.
Chile finished second in their group, falling only to a Dutch side that looks unstoppable right now. They knocked off a game but overmatched Australian side before a 2-0 victory over Spain so comprehensive that the Spanish - despite being defending champions and needing at least a draw to stay alive - basically quit on the game with half an hour left. Chile's attack boasts Alex Sanchez up front and is supported by Arturo Vidal, one of the best midfielders in the game. The team is set up to press high and not allow opponents time on the ball, which may be bothersome for Brazil's flair players.
Neymar will draw a lot of the attention, but I think the most interesting battle in this game will be in the center of the park between Vidal and Oscar. Brazil would do well to keep Oscar involved in the game, as he is capable of moments of individual brilliance but also links play through the team very well. If Vidal finds space to run free, he can hit them from long range or pick apart a defense with his passing. Neither Oscar nor Vidal is shy about throwing himself into a tackle, either. This won't be a direct one on one competition, but both players will be fighting the other to help their team control the midfield.
Colombia (winner group C) v. Uruguay (runner-up group D)
Colombia were drawn into what was regarded as one of the weaker groups in the tournament, and they summarily pounded Greece and Japan either side of a narrow victory over the Ivory Coast. Their defense is solid, led by captain Mario Yepes who - at 38 - is the oldest outfielder player at the current World Cup. Even in their one-goal win, it was an individual moment of brilliance that led to the goal; this is a difficult team to break down.
Forget interest in the World Cup; everyone with an internet connection has heard about Uruguay lately, after their star striker and part-time cannibal Luis Suarez bit an opponent for the third (!) time since 2010. Somewhat unsurprisingly, he has been suspended for the duration of the World Cup and beyond. Now manager Oscar Tabarez must decide if he wants to have the tireless Edinson Cavani working solo up front or if he will replace Suarez with the aging Diego Forlan and retain a two-striker system. No matter what is decided up front, the defense will be marshalled by towering skipper Diego Godin, whose expansive forehead is responsible for the goal that put Uruguay through.
Both of these reams have been dangerous going forward off of a base of defensive solidity rather than just throwing men at the goal. The longer the scoreless state persists, the better the chances for Uruguay to take a 1-0 win with a set piece. If they go behind early, though, they might find it a long road back against Colombia, especially with Suarez gone.