"We stuck at it, and had the courage at the end to go for the try ... it's just fantastic," Japan coach Eddie Jones said. "I had to look at the score at the end of the game to see if it was true or not."
Many who missed the match and woke to the result must have questioned their hearing, sanity or both. Japan with a solitary World Cup win, had beaten the tournament winners from 1995 and 2007.
Most at the ground gawped as Japan were awarded a penalty one minute from time. It was a gift and would give Japan an outrageous draw but Leitch went for an attacking lineout as the stunned crowd assessed the decision.
A rolling maul came down to a TMO decision. No try but there was time for a scrum. Japan had worked on superb clean striking and whizzed the ball to the right then the left and, with some calm passes and decisions, unpicked the Boks defence to put Hesketh in at the corner.
Ayumu Goromaru converted from the touchline when the scores were level, proving who could live with the final, fateful pressure.
Match highlights
The top 10 matches of 2015
10) Super Rugby final
9) Roberta Vinci over Serena Williams
8) The day-night test
7) Holly Holm stuns Ronda Rousey
6) Cowboys' golden triumph
5) All Blacks thrash France
4) Breakers win title at the buzzer
3) Williamson six gives Black Caps win over Australia
2) Japan stun South Africa
1) Revealed tomorrow
