All Blacks v Wallabies: Roger Tuivasa-Sheck should start in second test against Australia, says John Kirwan

All Blacks legend John Kirwan believes the time has come for Roger Tuivasa-Sheck's first start in the black jersey.

Injuries to David Havili (head knock) and Quinn Tupaea (knee) has left a gap in the No 12 jersey for the All Blacks.

While Jordie Barrett remains the favourite to be moved from fullback to No 12 – like he did in the first test against the Wallabies – with Beauden Barrett likely stepping in at 15, Tuivasa-Sheck is a more natural replacement in the midfield.

Speaking on Sky Sports' The Breakdown, Kirwan said starting the former Warriors captain on Saturday would be the best move for next year's World Cup.

"I don't think he (Ian Foster) will start Roger Tuivasa-Sheck at No 12 ... [but] I would like to see that," Kirwan said.

"Just throw him in at the deep end. We've got the cup in the cupboard, the Bledisloe Cup.

"We want to win the [Rugby] Championship but if you're thinking about World Cup, I'd like to see Roger Tuivasa-Sheck have a start.

"I think the biggest decision is what you do with Jordie Barrett, because then you change a whole backline.

"I think there are a couple of structural things in defence that we need to look at as well. Our outside-in defence has let us down across the Championship.

"But we've got the [Bledisloe] Cup, play Roger."

Roger Tuivasa-Sheck. Photo / Photosport

Kirwan's co-host Jeff Wilson agreed that Tuivasa-Sheck should feature on Saturday.

"I think Roger Tuivasa-Sheck needs to play in this test match.

"I've got concerns. We're getting found out in regards to what's happening on the outside, the links between our midfield and our outsides.

"There's not enough talk for me that's enabling guys to shift and guys are getting in some really bad angles.

"Will Jordan got found out, Caleb Clarke ... bad angles because I don't think there was enough communication, telling them where they needed to go. They were gambling."

Wilson added that bringing back RTS would also give the backline more stability.

"I honestly don't have a problem, the more I've thought about him (Tuivasa-Sheck) starting at 12 in this test match because then we haven't made any other changes.

"It's just the one. The only thing is you've got to find some more distribution and a kicking game, which David Havili was adding."

Tuivasa-Sheck has been back with Auckland in the NPC after his time in the All Blacks environment, where he made just one appearance in the third test against Ireland in July.

He scored a try in Auckland's 30-27 victory over Tasman over the weekend.