Men's Olympic soccer begins July 26, one day before the opening ceremony in London. Each team consists of an under-23 side with three overage players. Here's a breakdown of teams and players to watch at the tournament.
Great Britain- Group A
Team GB are competing at their first Olympic football tournament since 1960. There is a lot of history to the British side, both positive and negative. Only Welsh and English players are in the squad, and Wales along with Scotland and Northern Ireland expressed disapproval of the team.
Great Britain won gold in 1908 and 1912. They will look to secure another medal this time, and they brought a talented squad to the tournament. Legendary Manchester United midfielder Ryan Giggs is captains the team. Up front, his Welsh compatriot Craig Bellamy partners with Chelsea striker Daniel Sturridge.
Midfielders Tom Cleverly and Aaron Ramsey will be players to watch. Cleverly has returned to fitness after an injury-riddled season with Manchester United, while Ramsey has established himself as a first-choice playmaker at Arsenal after a career-threatening injury in 2010.
Uruguay- Group A
Uruguay won two gold medals in football at the 1924 and 1928 Olympics. They remain the only Olympic gold medals the country has ever won in any sport. Their football team have now qualified for the tournament again for the first time since winning gold 84 years ago.
The Uruguayans are bringing two of their most important strikers from the senior side in Liverpool's Luis Suarez and Napoli's Edinson Cavani. Palermo holding midfielder Egidio Arevalo Rios provides leadership in the middle as the third overage player.
World Football Magazine's South American football correspondent Tim Vickery told DW that the Olympic football tournament provides an important transition for youth national team players. "This is where the next generation of Uruguayans can push their claims for a place in the senior side," he said.
Vickery identified Gaston Ramirez and Nicolas Lodeiro as playmakers to watch. In defense Liverpool center back Sebastian Coates is expected to pair with Alexis Rolin. "The Italian press have dubbed him the new Thiago Silva, and he has got some of that about him," said Vickery of Rolin.
Jonathan Urretaviscaya, who Vickery said "has just a little bit of the Cristiano Ronaldo about him," is another exciting and dynamic player to keep an eye on. "This is a generation that Uruguayan football has very, very high hopes of," said Vickery.
Mexico - Group B
Mexico has solidified itself as number one in CONCACAF for the time being after victories in the 2011 Gold Cup and the Olympic qualifying tournament. The squad they are sending to London reflects the enormous talent within the country at the youth level, as only one player plies his trade outside Mexico.
Giovani dos Santos has played more than 50 times for the Mexican senior team
That one player is Tottenham Hotspur midfielder Giovani dos Santos, who has never quite found success at club level, but almost always impresses internationally and has long been a regular for the senior side.
Many players in Mexico's Olympic team have experience with the senior team, including midfielders Javier Aquino, Marco Fabian, and Jorge Enriquez. Over-23 defender Carlos Salcido brings the experience of his years in Europe playing for PSV Eindhoven and Fulham.
Brazil- Group C
No team is under pressure quite like the Brazilians. The Olympic football tournament is the only major international competition Brazil have never won, and if they come up short in London, head coach Mano Menezes may be out of a job.
Neymar will be Brazil's key player
The tournament holds extra importance because of Brazil's dearth of competitive games in the lead up to the 2014 World Cup, having already qualified as hosts. Brazil see the Olympics as an opportunity to get important players more experience for the future, and their squad selection reflects that. "This is a sketch of the World Cup team if we go through it man by man," said Vickery.
Forward Neymar, who led all scorers with nine goals in qualification, is expected to be the star of the tournament. In the center of midfield, Tottenham's Sandro will partner with new Spartak Moscow signing Romulo. Midfielder Oscar and forward Leandro Damiao will be other players to watch, and Vickery said the two work well together. Oscar scored a hat trick in the final of Brazil's victorious World Youth Cup campaign last year.
Japan- Group D
Olympic football in Japan has a long history and tradition according to Japan Times reporter Andrew McKirdy.
"When Tokyo hosted the  Olympics, at the time it was one of the first chances people got to watch top level football," he said in an interview with DW. "In Mexico City four years later they won bronze."
The Japanese squad for the Olympics, though, is somewhat muted. There is no Shinji Kagawa or Keisuke Honda, but McKirdy says Japan's emphasis for the tournament is on their young players. "They are the ones that qualified, so they are the ones that deserve to get the shot in London," he said. Indeed, Japan have only brought two over-age players, and four years ago in Beijing they brought none.
But Japan still boast a strong squad that has a shot at medalling. Five play in Germany, including midfielder Takashi Usami, who spent last season on loan at Bayern Munich. McKirdy said his quiet season with the Bavarian giants may have muted expectations about him, but he remains a dangerous player. The other player to watch is forward Kensuke Nagai (pictured at top). "He is very fast," said McKirdy, adding that he is in strong form at the moment for J-League club Nagoya Grampus.
Spain- Group D
Coming off the back of their third successive major tournament win, Spain will want to show that their talent extends to the youth level as well. A combination of senior side players and members of the 2011 Under-21 European Championship-winning side make Spain one of the favorites for gold at the Olympics.
Juan Mata, who scored in this summer's European Championship final win over Italy, will pull the strings in midfield. Another scorer from that game, Jordi Alba, will slot in at left back. Manchester United goalkeeper David de Gea and Athletico Madrid forward Adrian Lopez mean Spain are strong at nearly every position.
Other players to watch
Ryan Nelsen and Shane Smeltz, New Zealand - the iconic defender Nelsen will captain his country at the Olympics. New Zealand Herald and AP reporter Michael Brown calls him a "big influence on the side." Forward Shane Smeltz scored in the World Cup against Italy, and won the A-League golden boot in 2009. "Up front is where the strength lies with the team," Brown told DW.
Ji Dong-Won will be one of South Korea's players to watch
Ji Dong-Won, South Korea - an established member of the senior side, he has scored an impressive eight goals in 16 appearances for his country. The Sunderland striker can cause problems for opposing defenses with his knack for scoring in big games.
Abdelaziz Barrada, Morocco - the French-born midfielder plays for Getafe in Spain's La Liga. He scored 3 times in the African qualifying tournament, winning the golden boot. He was named to the tournament's best 11.
Mohamed Aboutrika, Egypt - the iconic midfielder initially retired from football following the Port Said disaster in February that left more than 70 fans dead. He made his return in March, scoring a hat trick in the African Champions League and qualifying his club, Al-Ahly, for the group stages of the competition.
Pajtim Kasami, Switzerland- the Fulham midfielder has not enjoyed a great amount of playing time at the club level, but he is a talented playmaker with speed and size who could make an impact with his versatility.
Dame N'Doye, Senegal - a regular with his country's senior team, the striker has been prolific for FC Copenhagen. He has scored 66 goals in 119 appearances for the Danish club since arriving in 2009, winning the golden boot this past season
Author: David Raish
Editor: Matt Zuvela