All Blacks great: Ardie Savea 'simply must be on the field' against the Wallabies

Ex-All Blacks halfback Justin Marshall believes his former side cannot face the Wallabies in Perth this weekend without the services of star loose forward Ardie Savea.

Plenty has been made of the make-up of the All Blacks' loose forward trio, with speculation swirling about captain Kieran Read moving from No 8 to blindside flanker to accomodate both Savea and openside flanker Sam Cane.

Savea, an openside flanker who can cover No 8, has been in career-best form in 2019, leading to an ongoing public debate as to how, if at all, both he and Cane can both feature in the starting side for the national team.

Marshall, who played 81 tests for the All Blacks between 1995 and 2005, told Fox Sports that Savea must start regardless of his role in the back row.

"The metres he's making through the middle are incredibly important to breaking down that aggressive defence because it gravitates players in toward [the] ruck and narrows them up," he said.

"You need a strong ball carrier. They definitely have to have him on the field and that puts pressure on the other two players in the loose forwards who then have to complement him."

The 46-year-old noted that the biggest issue around fitting Savea into the starting side, however, lay with Read's position in the side as captain.

"He's the captain of the All Blacks and he has only ever played No 8," Marshall said, despite the 119-test veteran having played four of his first nine All Blacks tests at blindside flanker and having previously played there for the Crusaders earlier in his career.

"That's a bit of a dynamic they have to work out because they lose a little of lineout superiority if they don't have a genuine jumper at 6. Sam Cane and Ardie Savea aren't really that.

"But they've got to work their way through it.

"For me, Ardie Savea simply has to be on the field."

Marshall went on to say that the All Blacks had struggled to adapt to suffocating defence systems in the early rounds of this year's Rugby Championship against Argentina and South Africa, which led to a tense 20-16 against the Pumas, and a 16-all draw against the Springboks.

"I certainly feel that — and the All Blacks are aware of this and it's why they're working hard on it — that the aggressive out-to-in deep defence, so the outside, the centre in particular and the wingers, coming up right in the eye line of the receivers and making them feel like that there's no space on the outside, the All Blacks are struggling with it a little bit.

"They're hellbent on trying to use their wingers and get them into the game - it's a strength of New Zealand rugby - but they're struggling to get them it to them at the moment.

"They have to work through that and get to the point where they are confident to be able to use the ball on attack and break that defence open, and at the moment they still haven't quite figured it out, so that is a vulnerability."

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