More than ever, it will be all or nothing for Brazil's men's national team in the Olympic football tournament.

Brazil has always been under pressure to win the gold medal, the only significant title it doesn't have in football, but in London there will be a lot more at stake for the five-time world champions.

Brazil will be one of the few teams with most of its top players, and failure at the Olympics will likely cost coach Mano Menezes his job ahead of the 2014 World Cup the nation will host.

There will be high expectations from everyone in Brazil, including fans, local media and football officials.

The Brazilian federation has already said that winning the gold is the national team's priority this year and hinted that a disappointing result will inevitably prompt changes as Brazil enters the final stretch of its preparations for the World Cup at home.

Most of the players in Brazil's Olympic team will likely be in the World Cup, too, and the competition in London will give many of the promising young Brazilian players a chance to prove their worth.

"We know that our final evaluation ahead of the World Cup will be done during the Confederations Cup next year, when we will play with a team which won't be restricted by the age limit," Menezes said after announcing Brazil's squad on July 5. "But it's obvious that we need to play well in the Olympics to reinforce the convictions that we have about the team so far."

Few teams will showcase their top players at the Olympics because it's played with under-23 squads and only three overage players per nation, but Brazil's young squad will include names such as Neymar, Lucas, Alexandre Pato, Paulo Henrique Ganso, Oscar and Leandro Damiao.

"We have a strong group, we are taking players who are regular starters for some top clubs today," Menezes said. "A lot of the young players will get a chance to start earning a spot in the squad. Something that wasn't certain before can start becoming a reality for them during the Olympics."

Brazil's overage players in London will be AC Milan defender Thiago Silva, Real Madrid left back Marcelo and FC Porto striker Hulk.

Many in Brazil praised the squad picked by Menezes for the Olympics, but there were critics, too.

"I don't agree with the players he selected," said former Brazil striker Romario, now a congressman. "He should've called players who are more respected abroad. There are plenty of other over 23 players he could've selected."

Among those in the list, Neymar is probably the one who was not doubted by anyone. The youngster is touted as the future of Brazilian football and the player expected to lead the national team at the World Cup. The Olympics will give him a chance to prove that he can indeed carry the country's hopes for the future.

"I'm very happy to have the honor of representing Brazil at the Olympics," the youngster said on Twitter after the final squad was announced.

He had already said that it will be a dream if he can help give Brazil the first gold in football.

The 20-year-old Neymar, who was in the list of 23 players running for FIFA's player of the year award in 2011, will be one of the tournament's main attractions, along with Britain midfielder Ryan Giggs.

Adding to the pressure for a good result in London, Brazil is heading to the games only 11th in FIFA's world rankings, the worst ever position for the five-time world champions.

"The pressure will always be there, we have to live with that," Menezes said. "But I don't think it's necessarily a bad thing, we can use that in our favor."

The team headed to London played four friendlies in preparation for the games, beating Denmark and the United States and losing to Mexico and Argentina.

Brazil won the Olympic silver in 1984 and 1988, and the bronze in 1996 and 2008, when Argentina took gold with Lionel Messi after beating a Brazilian team that included former two-time world player of the year Ronaldinho.

Brazil will be one of the favorites this year along with host Britain and Spain, which won the under-21 European Championship last year to clinch its spot in the Olympic tournament.

"Spain traditionally has done a good job preparing a youth team along with its main squad. It will also have some players from the team which won the Euros," Menezes said, adding that Mexico may also be included among the favorites in London.

Not many other traditional football nations will be competing in England. Of the 16 teams in the men's tournament, four will be making their Olympic debut - Senegal, Gabon, Belarus and the United Arab Emirates. Only three are past champions - Britain (1908 and 1912), Uruguay (1924 and 1928) and Spain (1992).

Brazil is in Group C along with Egypt, Belarus and New Zealand. It will face Egypt on July 26 at Millennium Stadium in Cardiff, Wales, then will play Belarus at Old Trafford on July 29 and New Zealand in Newcastle on Aug. 1.

Menezes has already acknowledged that Egypt will likely be one of Brazil's toughest opponents, especially because it will be its first. But he knows that beating its last opponent in an eventual gold medal match is the only thing that will really count for Brazil in this year's Olympic tournament.

He is confident it can finally be done.

"We are certain," Menezes said, "that we have a quality group of players who will give the Brazilian national team a chance to fight for the medal at the end."

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