#1 Lionel Messi (Argentina)

It doesn't come as a surprise that the most vital player in Saturday's clash between Argentina and Iceland will be Barcelona star, Lionel Messi. If it wasn't for his heroics against Ecuador in the final qualifying game, Argentina would've sat this World Cup out for the first time since 1970.
Often considered as the Greatest player of all time, he hasn't had any luck while playing with the national team as he went on to lose 3 consecutive finals with them. However, this time he would be looking to go one step further and cement his legacy by winning the World Cup.
His ability to decide the outcome of a game single-handedly is keeping the Argentine hopes of winning their 3rd World Cup title alive. On Saturday the scenario won't be any different as Messi will keep on worrying Icelandic defenders throughout 90 minutes with his dribbling and clinical ability to create spaces in the opposition half.
Iceland will have to come up with a special plan to stop the little magician if they want to start their World Cup campaign with a positive result.