The famous names are the same, but this Olympic men's soccer competition has proved to be so wild that speculating on which team will advance to the semifinals is nothing short of rash.

Brazil , which has never won an Olympic gold medal despite its glorious history as football's dominant nation, remains the firm choice to end that drought. But when the quarterfinals begin Saturday across Britain there will be many thinking that the host country, Mexico or even surprising Egypt might be able to lay claim to the title on August 11.

A key point to consider is that the Olympics is an age-eligible tournament. Each entrant can add three "overage" players to the roster -- ask Uruguay and Spain how that worked out -- but when a small roster of young players has to produce at the top level four times in 11 days, form tends to get lost in the process.

Brazil faces Honduras , the team that helped to shatter Spain's Olympic dream, at Newcastle after having completed the group stage with a perfect record. Emerging superstar Neymar has managed to ignore the daily rumors about a big-money transfer to put together an impressive exhibition of his skills. While Oscar, Chelsea's recent signing, is introducing himself to a new set of fans with a fine Games.

However, the Brazilians do have a major problem - the loss of their top-choice goalkeeper Rafael Cabral to a pre-Games injury has left coach Mano Manezes scrambling. Neto, Italian-based but hardly used and never a regular as Brazil developed this Under-23 team, has looked shaky in the first two group games. Gabriel got a start against New Zealand but had so little to do against the Kiwis that his performance could not be evaluated.

In contrast to Spain and Uruguay, whose overage stars flopped, Brazil has gotten an excellent showing from Hulk up front and Thiago Silva at the back. While Neymar often has looked the most likely to score, the goals have come from all places, often the result of excellent closing runs by defenders or midfielders after Neymar and Co. have split the defense.

Honduras, which has its own emerging star in New England Revolution's Jerry Bengtson, played smart defensive soccer to defeat Spain, then insured its chance to tackle the Brazilians by finishing with a draw against group-winners Japan . It's a large ask, but manager Luis Suarez's team has already ensured that it will go home as heroes.

Team GB seems to have gathered momentum after a shaky start and will undoubtedly have a huge crowd behind them against South Korea in Cardiff. It's a tricky match, however, because the Koreans clearly outworked all three of their group opponents and will hit the hosts with the same combination of huge effort and midfield pressure. Unfortunately for the Koreans, a lack of poise in front of goal - a long time bugaboo - has resurfaced. They should have beaten both Mexico and Gabon on possession alone, but both matches ended goalless.

Stuart Pearce's British bunch has been a polar opposite. At times forced into a very defensive posture, Team GB has been extremely good at cashing in its chances. Daniel Sturridge and Scott Sinclair have supported veterans Ryan Giggs and Craig Bellamy, while midfielder Joe Allen - said to be Liverpool's number one target - is winning over fans with his midfield prowess.

The real British star, however, is goalkeeper Jack Butland. He's made spectacular saves in every game to date, the reason why Team GB was able to walk the tightrope and emerge with a perfect record.

The other two quarterfinals offer contrasting storylines.

Egypt will be a sentimental favorite against Japan simply because their arrival in the last eight defied the challenge they faced just to get to London. After the Port Said stadium disaster shut down all football in the country, coach Hany Ramzy had to overcome the burden of preparing a team whose players have had no league football for months.

Ramzy smartly tabbed the veteran Mohamed Aboutrika as one of his overage players and has seen that pay off abundantly. Mohamed Salah has produced two huge goals, the equalizer against New Zealand and the first goal against Belarus, to complement Aboutrika's quality.

Japan opened with a stunning win over Spain, but like South Korea , has struggled to finish numerous chances. Yuki Otsu and Kensuke Nagai will need to be sharp against the Egyptians.

Mexico came to London with one of the best-prepared Under-23 teams, a group which started getting ready to chase gold by competing in last year's Copa America. While Luis Fernando Tena's side has not looked as good as it did on the way to the Games, the performance of Giovani dos Santos as team sparkplug has covered up the fact that Marco Fabian and Oribe Peralta have not been as dangerous as they can be for the young edition of El Tri. Goalkeeper Jose Corona matches Butland as a star to watch and the Mexican defense has been sound.

Mexico's defense will need to be in form against the fast, sturdy Senegalese who have their own star of the Games in forward Moussa Konate. With four goals in three games, Konate has been the only marksman for his team, but his goals have been superbly taken and perfectly-timed to keep Abdoukarime Diouf's eleven very much in the medal hunt.