The Springboks' performances during the Rugby Championship have been Jekyll and Hyde-like.
They were absolutely brutal in the physical exchanges (delete against the) with Argentina in Durban, before looking lost and helpless the following week against the same opponents in Mendoza.
The South Africans lacked the fizz and made a plethora of mistakes when they came up against the Wallabies in Brisbane. It seemed like they actually wanted to be on the Gold Coast for some fishing and to catch a wave or two rather than catching a ball or making a proper pass.
A week later, though, it looked like a totally different Springbok team against the All Blacks. They were far from the defeatist outfit who so tamely went down in Argentina. They were a team that mustered up the strength and the courage to make 240 tackles, most of them big ones. They then took their chances brilliantly with the 25-percent possession they had to work with and scored 36 points against the All Blacks.
In 2017 the Springboks were thumped 57-0 by the All Blacks in Albany, before narrowly losing to the world champions in Cape Town in a humdinger of a clash. It was a one-point defeat, but one that stung the Boks and may have been the catalyst for their win in Wellington.
"If you think back to what happened in Cape Town, it was a very emotional journey after that. We played our hearts out and we lost," prop Steven Kitshoff said this week. "Going into Wellington, nobody gave us a chance, but we came out fighting and got the win at the end of the day, which was really special. You could see it on the guys' faces afterwards, they were really chuffed with the win."
So why don't we see this sort of performance from the Springboks on a weekly basis? Why must the coach first threaten to resign or for the team to have their backs against the wall before they produce the sort of special effort that they delivered in Wellington? The most important question, though, might be how does Erasmus get the Boks to be consistently brilliant?
For starters, the victory in Wellington have given the Springboks a lot of self-belief and the spirit in the camp is great. The management and the players are a lot more relaxed. It's going to be important for the Springboks to try and replicate the mindset they had when they walked into the Wespac Stadium.
"We always prepare well for every Test we play. But the win gave the team a bit of confidence for the next couple of weeks ahead," Kitshoff said. "You can feel that there is a lot more energy, the guys are excited and pumped for what lies ahead.
"Every week is a big occasion, and you have to be up for it physically and emotionally. I think what we are trying to get right is being physical and in the opposition's faces and making the big hits.
"When it comes off, it feels brilliant. Our prep is to get that feeling when the kickoff comes and being switched on from the start."
The win in New Zealand was a big deal for the Boks. But the lessons that they took out of it could be priceless ahead of next year's World Cup.