Summer Olympics 2012 Predictions: Favorites Who Will Fail to Win Gold

Disappointment is part of the Olympics. 

You'll likely get caught up in the Cinderella stories, the broken records and the unforgettable finishes, but unfortunately, upsets are also a large part of every competition.

And with upsets comes failure. Athletes or teams that are favorites somehow don't walk away with the gold. It's not something that is fun to focus on, but it happens.

With that being said, let's take a look at the top athletes who have a good chance of taking a step back in London. 

Usain Bolt

Four years ago, when Bolt was running his way into the record books and our hearts, it didn't seem possible that he would ever lose.

And while he is still the favorite to take home gold in the 100- and 200-meter dash in London, he's certainly not a guarantee anymore.

A large part of that reason is his fellow Jamaican countryman, Yohan Blake. 

Less than a month ago, Blake ran a perfect race during trials, upsetting Bolt. While it will certainly take another perfect race, Blake has at least shown that he can pull off the upset, especially if Bolt comes in undetermined or gets a bad start, both of which are possibilities. 

Americans Tyson Gay and Justin Gatlin will also likely at least challenge Bolt. 

There's no question that Bolt is still the fastest man on the planet, but I wouldn't be surprised if he drops to silver in one of his two races. 

Brazil Men's Football

Led by Neymar, Alexandre Pato, Hulk and a slew of other world superstars, Brazil is the obvious favorite to take gold in football.

I agree the Brazilians are the best team, but even with the under-23 teams, there is going to be an insane amount of firepower around them.

Spain has Premier League stars David de Gea and Juan Mata, not to mention Jordi Alba, Javi Martinez and Adrian.

Uruguay is an underrated squad, as it has brought in veterans such as Luis Suarez and Edinson Cavani to go with a talented midfield.

Great Britain is solid and will be playing in front of a home crowd. Switzerland and Mexico even have some intriguing pieces. 

Brazil is good, but I see an upset looming. 

Michael Phelps

Phelps will break all the records he has left to break, but I don't think he's going to sweep his events. 

He's going to struggle against Ryan Lochte, the world record holder in the 200- and 400-meter individual medley, but the Lochtenator is the favorite in those events, so that doesn't count. 

Instead, I'll go with the 200-meter butterfly as the event Phelps will be upset in. 

Takeshi Matsuda took the silver at the 2011 World Championships in Shanghai, losing to Phelps by less than a second. I wouldn't be surprised if he gets over the hump and takes home a gold for Japan. 

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