15 greatest upsets in Summer Olympic history

'Welcome to Hell' at Rio Olympics
'Welcome to Hell' at Rio Olympics

Every four years, the greatest athletes in the world compete in the Summer Olympics, as they try to bring Olympic gold to their country. Competing in a wide variety of events, these athletes have to beat the best in the world in order to get the glory, and sometimes, it does not work out the way they planned.

Each Olympics are known for their own signature moments, and often times, those moments include some incredible upsets. Whether it is in team sports like basketball, or individual events like a marathon, the upsets are what make each Summer Games special.

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The 2016 Rio Olympics will kick off on Aug. 5, and there are sure to be some major upsets once again. The great thing about Olympic competition is the unknown, and while there are favorites who are expected win heading into the Games, there are also unknown athletes from smaller countries who are training just as hard to win.

As we take a look at the 15 greatest Summer Olympic upsets of all-time, we had to go all the way back to 1900, the second modern Olympic Games. Over the last 116 years, there have been plenty of unbelievable accomplishments, but it is the upsets that seem to stick in the minds of sports fans when they think of the Olympics.

With that said, take a look at the 15 greatest upsets in Summer Olympic history up above.

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