No, we are not talking about Billy Mills in the 1964 Olympic 10.000. Not even close. The greatest upset in track history was the women's mile in the indoor dual meet with the Soviet Union in March 1972 in Richmond, Virginia. The Russians, Tamara Pangelova and Ludmila Bragina, had just run 1-2 in the European Championships 1500 the previous week with Pangelova setting the world record. Bragina would win the Olympic 1500 four months later. The Americans were five-time world cross country champion Doris Brown and high school girl Debbie Heald who had taken the first two spots in the US Championship in Madison Square Garden three weeks earlier. Tamara, Ludmila and Doris were 28 and 29 years old, Debbie was 16. The Russians were coached by their national coaches. Doris was coached by the legendary Ken Foreman. Debbie was coached by her 4th and 5th grade teacher mostly on the elementary school playground after school.
Go to YouTube, “Debbie Heald vs. the Russians” to see the video. I think you may agree with my premise.