Argentina have shown flashes of exactly what they're capable of when they hit their stride, but without setting the world alight either. Two 1-0 wins against Uruguay and Jamaica have seen them through to this stage, but there does seem to have been a slight hangover from the fact that they dominated Paraguay in their first match, and ended snatching a draw from the jaws of victory by conceding two goals to give up their early lead. Colombia, another of the teams that should have a good shot at this title, are also in a bit of flux at the moment, and coach Jose Pekerman is left with a difficult decision to make: does he drop captain Radamel Falcao who has carried his poor form from his season with Manchester United into this tournament, and simply doesn't look like the player he used to be anymore? His replacement would be Jackson Martinez, who is in much better form and gives them a real threat up front against an Argentina defence that should be considered the weak point of an otherwise incredibly talented team. Now that we've reached the quarter final stage, this is one of the biggest matches of the summer, and will feature two of the most talented players on the planet right now, Lionel Messi and James Rodriguez. That alone makes it worth staying up for, especially of a Friday night.