He attended three World Cups, of course, as a player with Scotland in 1995, 1999 and 2003 and knows a repeat of Japan’s Saturday heroics against his home nation would jeopardise their hopes of reaching the last eight.
But Redpath, 44, admits he has never once before witnessed the sort of scenes that occurred in Brighton when the dumbfounded Springboks were left utterly stunned by a 34-32 defeat to the Pool B minnows.
“The odds were 500/1 or something like that and I do think it’s the first time I’ve jumped out of my chair for a long time,” he said.
“It was outstanding. To see Japan’s knowledge, execution, skills and commitment to it were second to none.
“Maybe South Africa thought they could just bully them and run over them. But the tenacity and commitment Japan showed was outstanding.
“They have always been a fit side anyway but the energy and detail they had…”
Redpath will be covering this afternoon’s game for radio as Scotland open their World Cup campaign at Gloucester, where he started his coaching career in 2009.
It would be remarkable if Japan could back up their triumph so quickly but he said: “The second tier nations have improved in the last four years.
“The short turnaround is never easy but in general terms the second tier have improved since the last World Cup and are coming through all the time.
“The big thing is you can’t take anyone lightly any more and Scotland will know that.”