When Waldemar Cierpinski won the marathon gold medal at the 1976 Olympic Games in Montreal, it was one of the biggest shocks the event had ever seen.
The red-hot favourite had been Frank Shorter, the defending champion, but the East German Cierpinski emerged from the pack to record his first major international success.
It was a remarkable turnaround for Cierpinski, because he had had to run a marathon nine weeks before Montreal to finally convince selectors that he was worthy of his place on the plane.
Like many world class distance runners, the circumstances of his childhood played a major part in his progress.
Similar to Haile Gebrselassie, he needed to run six kilometres every day to get to and from school, and consequently built up terrific aerobic reserves.
In his teenage years he trained as part of East Germany’s supremely disciplined regime, and was recording world class times by his late teens.
He had run only two career marathons a year before his Montreal gold medal, but once he crashed onto the international scene by defeating Shorter, his training regime became even more intense.
By the time Moscow came around he was among the favourites, and did not look flustered in the early stages when the Mexican Rodolfo Gomez surged into the lead.
Dutchman Gerhardus Nijboer briefly seized the lead two thirds of the way through the race before Cierpinski claimed an advantage he would never let go.
He went on to win in a relatively slow time of two hours 11.03 seconds, but it was enough to see him enter the record books alongside Ethiopian great Abebe Bikila as a back-to-back Olympic marathon champion.
He was denied the chance of a hat-trick when the Eastern Bloc countries boycotted the 1984 Olympic Games in Los Angeles.