In boxing you usually have a puncher's chance. The bigger shock was how Douglas dominated Tyson. Although Douglas was always considered talented and was really a good matchup for Tyson and was now motivated for the first time in his life. Tyson was a wildman in Japan throughout that week.
You really didn't have that with the Russians. They were more than pros because their training regimen was longer and more difficult that the NHL and if the NHL pros weren't so dirty the Russians would have dominated every matchup against them. Furthermore, the Russians were beating teams by double digits...in freaking hockey. And they beat the US team in an exhibition 10-3 days before the Olympics started. And the USA team had not been very good in a long time and was filled with college kids, almost all of whom never made it to the NHL or lasted in the NHL (perhaps the best NHL player was Neal Broten who didn't play much for the USA team).
I would probably add Francis Ouimet's victory in the 1913 US Open as he was an amateur from poor beginnings playing against world renowned pros like Harry Vardon and Ted Ray. Back then, golf professionals' main competition came from amateurs of wealthy and prestigious backgrounds who didn't want to turn pro because pros were kind of considered carny freakshows. Poor amateurs who played competitively didn't exist and for Ouimet to win and beat Vardon and Ray at the age of 19 years old people didn't think was possible.
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