1) Thibaut Courtois,22, Belgium
A lot of experts are putting their money on Belgium calling them the 'Dark Horse'. The chief reason for that is presence of players such as Eden Hazard, Romelu Lukaku and Marouane Fellaini who can break down any defence single-handedly.
But, 22-year-old goalkeeper Courtois could turn out to be the X-factor for the Belgian team.
He has had an outstanding La Liga season, where he recorded 20 clean sheets and averaged only .65 goals allowed per game, both of which were the best figures in the league.
He is called 'Octopus Child' by his fans for his ability to stop balls that come hurtling towards his post.
Despite Belgium's defence being seen as a weak link, Courtois ensures their last line of defence is in extremely safe hands.
2) Raphael Varane, 21, France
Varane played a central role in Real Madrid's Champions League triumph. Announcers Gus Johnson and Eric Wynalda referred to Varane as "one of the best young defenders in the world" during the broadcast.
He will be a crucial cog in the French juggernaut with their two most experienced defenders Patrice Evra and Bacary Sagna having crossed the threshold age of 30.
3) Victor Moses, 23, Nigeria
The 23-year-old Nigerian has been blazing down the wing for Chelsea and Liverpool in the English Premier League for the past couple of seasons.
Moses along with Peter Odemwingie and Obafemi Martins will be a big part of the team's offence.
If Nigeria are to advance from Group F, a lot will depend on whether or not Moses can unlock the defences of Bosnia-Herzegovina and Iran. With his pace and dribbling skills, he could also give Argentina's ageing defence major headaches.
4) Xherdan Shaqiri, 22,Switzerland
Shaqiri spent a long and excruciating wait at Bayern Munich this season trying to cement a berth in the first team. Rumours are abuzz that Liverpool are keen on acquiring the attacking midfielder.
He is sure to be the focal point of coach Ottmar Hitzfeld's game plan in Brazil. Short in stature, Shaqiri has a powerful game and is difficult to stop once he gets into his groove.
He has a powerful left foot. In the past two years, Shaqiri has totalled 18 goals and 18 assists in all competitions.
5) Julian Green, 19, United States of America
Coach Jurgen Klinsmann shocked everyone by naming Julian Green ahead of Landon Donovan in the 23-man-squad. Green recently graduated into the Bayern Munich squad after impressive performances during his stint with club's reserve side.
This 18-year-old winger doubles up as a striker for his club. He has the pace to outrun most defences and the technique to outsmart the best defenders.
There is a strong chance that the teen will figure in most of Klinsmann's plans.
6) Joel Campbell, 21, Costa Rica
The striker scored nine goals in all competitions for Olympiakos this year, including one against Manchester United in the Champions League Round of 16. He will be the team's go-to player.
The Costa Ricans are clubbed with Uruguay, England and Italy. If they are to make it out of the group stage, Campbell will have to pull his weight.
He came under heavy criticism for his diving during CONCACAF match against the US. With his talent, he should not have to rely on theatrics and should focus on stunning opponents with his lightning speed.
7) Teofilo Gutierrez, 29,Colombia
When you think Colombia, you think Radamel Falcao. But with Falcao out with injury, Gutierrez will have to pull up his socks.
He's always played second-fiddle to Falcao in the national side. He plays second fiddle for his club River Plate, but opponents would do well not to underestimate him. He has scored 11 goals in 27 games for Colombia.
His technical prowess and ball retention abilities are his greatest assets, but his team's chances will largely depend on how well he handles the pressure in Falcao's absence.
8) Fernandinho, 28, Brazil
Fernandinho does not come into the tournament with a humongous reputation like Neymar and Hulk, but the Manchester City central midfielder is one of the best in his position. His box-to-box running and team-first persona have made him an ideal partner for Yaya Toure at City.
9) Sejad Salihovic, 29, Bosnia and Herzegovina
The captain of the German club 1899 Hoffenheim is a name that quite a few ardent fans also aren't aware of. But, what makes the 29-year-old such a big asset is his versatility. He can play left back, left winger and defensive midfielder.
His is also a very popular leader and most teammates consider him down to earth and fun to be around.
Should Bosnia end up being in a penalty shootout, trust Salihovic to step up and coolly slot home his kick. In the Bundesliga this season, seven of his eight goals came via penalties (the exception being a free-kick against Hertha Berlin).
10) Keylor Navas,27, Costa Rica
Goalkeeper Keylor Navas is having a world-class season. He leads La Liga in saves made (109). He made four saves in a 1-1 draw against Barcelona. He denied Real Sociedad seven times in a 0-0 draw.
He has a chance to emulate the heroics of Luis Gabelo Conejo, who shone at the 1990 World Cup.
11) Julian Draxler, 20, Germany
The German sensation is grabbing headlines worldwide with his attacking exploits, especially long range stunners. The youngster has a great imagination and an eye for goal.
Germany has no scarcity of attacking midfielders, but Draxler may still play a crucial role as a second striker to veteran Miroslav Klose, who has 14 World Cup goals - just one short of topscorer Ronaldo.
12) Oribe Peralta,30, Mexico
Mexico had a rough ride in the qualifiers and managed to scrape through despite registering only two wins in CONCACAF's final round.
Peralta scored 10 goals in qualifying and Mexico will require a lot more from him in Brazil.