15 greatest upsets in Summer Olympic history

6. 1952: Runner wins marathon on a whim

It is not often that a runner can decide to run a marathon on a whim, and then go on to upset the entire field who trained for it. That was the case in the 1952 Helsinki Olympic Games, when Emil Zátopek showed up for the race a few minutes before it was to begin. Zátopek would end up lapping the field, which included favorite, Jim Peters of Great Britain. Peters has been called the greatest marathon runner of all-time, but on this day, it was Zátopek who would lead the field.

To make this story even more of an unlikely tale, Zátopek almost did not run in the marathon due to his doctor. His physician recommended he skip the event due to the fact he had an infection, and running could prove very costly to the runner. Zátopek disregarded the advice, and the rest is history.

Zátopek had a legendary 1952 Olympics, which included him winning multiple gold medals. It total, the Czechoslovakian runner won the gold in the 5,000m and 10,000m to go along with his win in the marathon, a trifecta that will probably never be repeated.

The “Czech Locomotive” attempted to defend his marathon gold medal in 1956, but he was hospitalized with a groin injury for six weeks. Although he began training as soon as he left the hospital, he never was quite right, and finished the race in sixth place. He retired the next year.

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