The Wallabies' much-maligned scrum turned on the power to leave All Blacks skipper Richie McCaw frustrated and scratching his head. Australia's new-look scrum, which featured Scott Sio in his run-on debut at loosehead prop, was expected to be a weakness for the home side at ANZ Stadium on Saturday night as they carried two openside specialists David Pocock, playing at No.8, and Michael Hooper.

But it was anything but a weakness as the All Blacks' pack wobbled in the Wallabies' 27-19 victory in the Rugby Championship decider, which set up a Bledisloe Cup winner-take-all Test at Eden Park on Saturday. McCaw struggled for answers when asked what happened to the All Blacks' scrum.

"I'm actually not sure. It was a bit frustrating, but I'm not sure what the story was ... I'm not sure," he said.

All Blacks coach Steve Hansen stepped in to help his skipper out.

"A lot of things [went wrong]. I think we'll need to have a look at the tape and have a good look at that and get some feedback from the guys that are out there as well," Hansen said. "We thought we'd fixed it [scrum] at half-time, but clearly we hadn't. We just weren't operating as an eight, we were operating individually and off balance."

Wallabies tighthead prop Sekope Kepu said the challenge will be to front up again next week.

"They will go back and I'm sure they will re-group and be better and we've just got to be ready for that and keep trying to improve," Kepu said.

Wallabies hooker and captain Stephen Moore was full of praise for Australia's new scrum coach and former Argentina rake Mario Ledesma.

"It's good for me having a hooker as a coach because he played in four world cups and there's not much he hasn't seen in those dark arts," Moore said. "I've picked a hell of a lot up already ... he's very passionate about the scrum."

Moore said the Wallabies' scrum was a work in progress.

"We'll look at the video of this game and there'll be heaps of things to work on," he said. "There's eight people involved and everyone is always going to have stuff to work on."

Sekope Kepu and Scott Sio combined to produce a solid scrum © Getty Images

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