Schalk Burger admitted losing the ball in his own 22 was the turning point in South Africa's loss to New Zealand in the semi-final at Twickenham.
The Springbok flanker was turned over by Dan Carter as South Africa were put under pressure at a scrum and New Zealand took advantage to score their second try through Beauden Barrett, with Bryan Habana also sin-binned for an intentional knock-on in the build-up.
That allowed New Zealand to take the lead back, and they didn't relinquish it, as South Africa's lineout misfired in the closing stages.
But rather than blaming the poor set-piece, Burger took responsibility for his error and felt it was the key moment in the game.
"I think the lineouts that we lost didn't help. It created pressure and made us defend a bit more," said Burger.
"But there are so many variables. The biggest one was me carrying and losing the ball in our own 22, they scored seven points. It was probably the turning point in the game.
"It's not only lineouts, it's probably my mistake. Credit to them they got a drop goal from Dan just after half-time which pretty much got momentum going for them.
"We created opportunities and there was never going to be a lot in it but we came up two points short.
"I have seen this movie before and it's bloody horrible. Unfortunately for us New Zealand were just a little bit better."