Midfielders:
Sung-Yong Ki (South Korea)
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South Korea's hopes will mainly be resting on the shoulders of their superstar Heung-Min Son, but the Tottenham-man will not be able to carry his team to glory by himself.
One of his main supporters in the team will undoubtedly be Sung-yong Ki. The Swansea player's contract will expire during the World Cup and he will be eager to use the tournament as a platform to impress possible employers.
Ki will be at the core of the Koreans' build-up play and will, therefore, carry a lot of responsibility if his team are to make a deeper run into the tournament. His Premier League experience, along with his fantastic passing ability, will certainly require his opponents to be at the top of their game.
Aaron Mooy (Australia)
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Aaron Mooy is largely under-rated, considering his huge contribution to Huddersfield's recent survival bid in the Premier League. The Australian will bring some much-needed quality in the middle of the park for his side at the World Cup.
Whether Mooy will be able to guide his team to the knock-out stage, is questionable, but if Australia are to cause an upset in Group C, he will have to be at the top of his game.
With France likely to win the group, a tough battle between Peru, Denmark and the Socceroos for second place is to be expected. It remains to be seen whether the Australian will grow with the challenges he faces, but he could certainly be a difference-maker in Russia.
Shinji Kagawa (Japan)
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Japan's national team has provided Shinji Kagawa with some much-needed relief from five difficult years at club level. Leaving Dortmund after his initial stint as a hero, his move to Manchester United and subsequent return to the BVB have been less successful.
Developing into a bit part player throughout the years, his status in Japan national team has never been in doubt. The World Cup will provide Kagawa with the opportunity to show the world what he's still capable of, a welcome challenge for the attacking midfielder.
Kagawa's work-rate and ability to unlock opposing defences will be the 'X-factor' for a well-balanced Japanese side, hoping to battle their way through to the knock-out stage in a tough Group H.