LISBOA, PORTUGAL - JUNE 07:  Cristiano Ronaldo of Portugal reacts during the friendly match of preparation for FIFA 2018 World Cup between Portugal and Algeria at the Estadio do Sport Lisboa e Benfica on June 7, 2018 in Lisboa, Portugal.  (Photo by Quality Sport Images/Getty Images)

Ranking the 7 World Cup One-Man Teams on Their Chances of Success this Summer

The World Cup is only one day away, and teams are settling in to their respective home bases in Russia as they finalise their game plans for their opponents.

But for some nations, the game plans may lean heavily on their one and only 'star' player - the one man who will make or break their World Cup campaign. Let's take a look at seven of those nations to see who will have to carry the weight of their team - and nation - at the 2018 World Cup.

7. South Korea - Son Heung-Min

Tottenham’s Son Heung-Min has become a key player for his side over the past two seasons, sharing the goal scoring burden with Harry Kane. For South Korea though he’s the standout player and is likely to be deployed in a more central role than he is used to at Spurs.

He will have some familiar company with Swansea’s Ki Sung-Yueng in support, but he only made 25 appearances for the Swans this season as they were relegated. 

With Germany and Mexico for company in their group, South Korea are likely to struggle from the off and it would be a surprise for them to pip Mexico to a second place spot. 

Predicted Exit: Group Stage

6. Egypt - Mohamed Salah

Egypt has been sweating on the fitness of Liverpool's talismanic forward Mohamed Salah since his Champions League final injury. Salah returned to training just in time to feature for his country at the World Cup, but he is unlikely to be at full fitness which could hinder his impact at the tournament. 

Salah will have several Premier League stars in support including Arsenal anchor Mohamed Elneny, Stoke's Ramadan Sobhi and West Brom's Ahmed Hegazi, but none of them are at the same class as the forward. 

Finishing as the second highest scorer in Europe this season behind only Lionel Messi, Salah could cause plenty of problems for Saudi Arabia and Russia. Egypt have only been to the World Cup once since 1934 though, and will have to face Uruguay as well as the host nation who will be buoyed by their home fans.

Predicted Exit: Group Stage

5. Costa Rica - Keylor Navas

Real Madrid goalkeeper Keylor Navas will be the anchor of Costa Rica's defence and will offer a huge boost to their hopes. They did emerge from the group stage at the last World Cup at the expense of England and Italy, which was no small feat. 

Navas will have support up top with Arsenal’s Joel Campbell and Sporting Lisbon’s Bryan Ruiz expected to lead the line. There’ll also be a familiar face in front of him in the form of Celtic defender Cristian Gamboa.  

Costa Rica will fancy their chances to cause an upset against Switzerland and get past Serbia, but will struggle against Brazil - as will most teams in the tournament. However, this isn't the same fairytale team from the 2014 World Cup - and their performances in recent friendlies against England and Belgium suggests getting past the group stage will be tricky.

Predicted Exit: Group Stage 

4. Iceland - Gylfi Sigurdsson

Iceland were one of the shocks of the 2016 European Championships, famously eliminating Roy Hodgson’s England as they made the quarter-finals. Everton’s £45m man Gylfi Sigurdsson is the heartbeat of that side, offering both goals and assists. Backed by the infamous Icelandic clap, they sailed through qualifiers and are hoping to cause a few more upsets. 

Sigurdsson will have newly promoted Cardiff midfielder Aron Gunnarsson and Burnley star Jóhann Berg Guðmundsson in support of his cause as well as a few Russian Premier League stars who will be familiar with the environment.

They have a tough group and face tricky tests against Argentina, Croatia and Nigeria. The strong competition could blow the group wide open but Iceland are going to need a few more big displays to get out of the group.

Predicted Exit: Group Stage

3. Denmark - Christian Eriksen

Denmark qualified for the World Cup courtesy of a crushing 5-1 away victory against the Republic of Ireland in the playoffs. They hadn’t been that impressive prior to that game though, finishing behind Poland in their qualifying group. They will be hoping for some inspiration from Tottenham star and Real Madrid summer target Christian Eriksen. 

Eriksen will be joined by Leicester City keeper Kasper Schmeichel and Chelsea defender Andreas Christensen. Sadly there was no place in the final squad for Nicklas Bendtner though, who picked up an injury shortly before the teams were announced. 

France will likely prove too strong for the Danes but with Australia and Peru making up the rest of their group they should be able to get into the knockout rounds. 

Predicted Exit: Round of 16  

2. Poland - Robert Lewandowski

Poland are ranked eighth in the FIFA World Rankings going into this World Cup. It’s a position that really flatters the Eastern European side who are on good form but are punching above their weight. Robert Lewandowski is reportedly looking to leave Bayern Munich this summer and will want to put himself firmly in the shop window with some star displays for his native side. 

Lewandowski has the strongest supporting cast so far with Napoli striker Arkadiusz Milik, Wolfsburg wide man Jakub Błaszczykowski and Juventus keeper Wojciech Szczęsny joining him in the Poland side.  

There are potential pitfalls in Japan and Senegal but given their current form only Colombia should cause them problems in the group stage. There’s a good chance they’ll be matched with England or Belgium in the first knockout round so they won’t be going beyond that. 

Predicted Exit: Round of 16

1. Portugal - Cristiano Ronaldo

A little harsh on the European Champions but Cristiano Ronaldo is comfortably head and shoulders above his teammates. Before the 2016 triumph, the international scene had been the only elusive one for Ronaldo as Portugal struggled to match his level. In a side that still contains the likes of Bruno Alves, Pepe, Ricardo Quaresma and Jose Fonte (all over 34-years-old), there is a distinct lack of new talent in key positions. 

There is at least experience in their side and Ronaldo will be backed by some promising young talent like Manchester City's Bernardo Silva and AC Milan's Andre Silva.  

They will likely come up short against a Spain squad with an embarrassment of talent, but should exit the group ahead of Iran and Morocco. With a top heavy Uruguay in the round of 16 and off the back of their European triumph Portugal should make it to the quarter-finals.

Predicted Exit: Quarter-Finals