"We succumbed to scoreboard pressure while our failure to convert pressure into points gave them increasing hope that they could somehow sneak a victory," said Burger.
"It doesn't matter how much rugby you play, if you don't build scoreboard pressure on the opposition then you can end up losing the match," he said.
That contingent are all four years older now, with a good number on the wrong side of 30, and Burger says that experience is vital in handling the pressure of a knockout game.
"To state the obvious, when you are younger, you only know what you know. When you are older you have experienced a few losses and the pain that comes with them.
"The biggest thing for us is that we have a calmness about us," the 32-year-old said. "We draw a lot from the younger players' energy, and they have got to bring the dynamism while we have to bring the leadership."
Burger, his humour restored once the conversation steered away from "9-11", said the 2015 campaign was a microcosm of his life as a Springbok since he made his debut in 2003 against Georgia in Sydney.
"This World Cup has been a lot like my career with its ups and downs, the setbacks, the good wins and the test of character," he smiled.
"We started with the most famous loss in World Cup history against Japan and after that the next two weeks were probably my toughest in 12 years as a Springbok," he said.
"What's important about this group is we pressed the reset button after that loss and we came back fighting, and we will fight to the death against Wales. We have to, because we know they are going to do the same."