Tim Cahill vs Ron Vlaar
Tim Cahill has no secrets as to where his strengths and weaknesses lay. He doesn't have roar acceleration or technique that scares defenders, but he is deadly in the air. He is often much shorter than the defenders he is marked by, but somehow he still manages to win the headers. He proved that scoring with a header against Chile, to score in his third World Cup for Australia, more than any other player for the Kangaroos.
Aston Villa defender Ron Vlaar will be tasked with stopping Cahill and his aerial threat, Australia will look to get the ball down the flanks and cross in for the former Everton and Millwall midfielder. Therefore Vlaar will need to cope with Cahill's threat and equal if not beat Cahill in the air more than not. Should he be able to o that, Australia's main attacking threat gets nullified and Netherlands will feel very confident with keeping a clean sheet.
Arjen Robben vs Mile Jedinak
Mile Jedinak captained Crystal Palace to survival last season, and his performances in defensive midfield made the club difficult to beat. Jedinak is looking to do the same with Australia, and his performances will be integral in how they fair against the 2010 finalists Netherlands and Spain in their last two group games. His role will be vital in covering his full backs, and making it a two to one in the Australia favour to prevent the Netherlands' forward play.
With Lens on one wing, and the confindent Robben on the other, he will have his work cut out. It is no secret that Robben loves to play on the right and cut in on to his favoured left foot, therefore he likes to run into the area where the defensive midfield is normally covering. Should Robben beat Jedinak and get the ball on to his left foot on the edge of Australia's box, then danger can insue for the team from the CONCACAF region. Jedinak will need to play a captains role, otherwise Robben can have a lot of joy.
Ryan McGowan vs RVP
Van Persie has been outstanding in the Orange shirt of late, he has scored ten goals in his last nine matches for his country. There is no doubt that he is a player that Australia will have their work cut out in stopping. That role is likely to fall to Ryan McGowan, who is going to come into Australia's starting team form the one that lost to Chile in their first match. There is not a centre-forward in world football that is in better form at international level than the Manchester United man, and McGowan will need to be at his absolute best to stop him in Porto Alegre on Wednesday afternoon.