Olympic rules state all players must be 23 and younger I think apart from three. You're allowed three overage players. I strongly think Brazil will be winning this. It's not about country vs country now, it's about the youth. Brazil's youth were awesome against US, they have the likes of Neymar, Hulk, Danilinho, Lucas etc. With their overage players probably going to be Marcelo, Silva and X (not sure on last), they'll be incredible. Who do you think is winning? Spain? Most of their awesome players are over 23 (Iniesta, Xavi, Xabi Alonson, Villa, Torres, Puyol, Pique, Ramos, Arbeloa etc), however, they did win Euro under 21's.