All Blacks coach praises 'smart' Rassie Erasmus for making 10 changes in Perth

South Africa's head coach risked hampering their title aspirations by switching up the team which had thrashed Australia 33-7 a week earlier.

Just five players remained from that starting XV as Erasmus put building squad depth ahead of the 2027 Rugby World Cup over Rugby Championship hopes.

However, the gamble paid off as the Boks went two from two in the competition with yet another bonus-point victory over the Wallabies.

They overpowered the hosts for the second week running by securing a comfortable 30-12 triumph in Perth on Saturday.

"The one thing that Rassie and his team has done extremely well is they've built depth over a four-year cycle," Robertson told reporters.

"If you look, I think it was the first time, the first World Cup, he had lost quite a few chess matches in there but he blooded some great young players that gave them the depth that was required.

"The World Cup squad is so hard to pick, they left some great players out, and that's where you need to get to.

"So I don't think it's brave, it's just smart to stay the course. He obviously did that last weekend, building depth."

It will be a fascinating battle between the two head coaches and no doubt Erasmus will seek to get a rise out of Robertson ahead of the first Test, with the Springboks boss known for his mind games.

"Wouldn't want to go down [that route] too far, just in case," the All Blacks head honcho joked.

"We just play what is in front of us really. I know Rassie, played against him and he's one of the personalities of world rugby isn't he? I enjoy his commentary.

"I bet everyone enjoys a press conference with him so looking forward to locking horns."

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