Group G - Germany v. Portugal
12:00 EST / 5:00 BST
Germany enters this year's competition with a ton of talent, but lingering question marks brought about by injuries. Marco Reus and Marcel Schmelzer will miss the tournament entirely, and Bastian Schweinsteiger, Philipp Lahm, and Manuel Neuer have all had injury issues in recent weeks. Still, the team must be considered a top competitor at this year's World Cup.
Most of the press surrounding Portugal has been, and will continue to be, concerning the health of Cristiano Ronaldo. The Real Madrid star has been suffering from tendinitis in his left leg, and though he is expected to play, his fitness will be a huge question.
Group F - Iran v. Nigeria
3:00 EST / 8:00 BST
On a day with two tantalizing match-ups, this encounter likely won't draw much neutral interest.
Iran are perhaps the biggest surprise inclusion in the World Cup this year. They qualified as the fourth best team in Asia, and have very little personnel recognizable to those not familiar with Middle Eastern football. If they are to take any points from the group stage, this match is where it must happen.
Nigeria won the African Cup of Nations in 2013, and will look to build off that momentum in a group that is less than terrifying. Former Everton center-back Joseph Yobo will receive his 100th international cap if he plays in all three of Nigeria's group stage games.
Group G - Ghana v. United States
6:00 EST / 11:00 BST
The Black Stars may be the most dangerous African team in this World Cup, and might be a favorite to advance to the knockout stage in some other groups. But they're stuck in Group G, and have a big hill to climb. Andre and Jordan Ayew, Kevin-Prince Boateng, and captain Asamoah Gyan are all legitimate goal threats, and midfielders Sulley Muntari and Michael Essien have a tremendous amount of European experience. If the Ghanaians can keep the ball out of the back of their own net (which may be a big if), they can do damage.
Tim Howard and the Stars and Stripes had a strong showing through qualification in the CONCACAF region, but, like the Ghanaians, were not helped by the draw. Howard will have to be strong if the USA are to advance, as the Yanks back-line is inexperienced and suspect at times. They will rely on Toronto FC midfielder Michael Bradley to create attacks, and Seattle Sounders forward Clint Dempsey and Sunderland striker Jozy Altidore to put away those chances. If those players can fill those roles, the US may be able to sneak out of Group G.