World Cup worry? All Black boss says Kieran Read still on comeback from operation

Kieran Read will get better by the World Cup.

That's the assurance from All Blacks assistant coach Ian Foster, who made a surprising claim that the under-pressure captain is still on the comeback trail from his back operation in late 2017.

Read will lead the All Blacks into Saturday night's test against Australia in Perth in a loose forward combination under constant scrutiny.

There are strong suggestions Read will be shunted to No. 6, with Ardie Savea taking his long-held spot at No. 8.

But if so, there are no indications as to whether this would be regarded as the top World Cup combination, with the All Blacks set to take their selection and tactical subterfuge into the tournament itself.

But Foster suggested Read is still to hit his physical peak.

Spilled...Kieran Read still wasn't physically right against the Springboks. Photo / Photosport

"In the last three months we've seen a big rise in the quality of his game," Foster told Newstalk ZB's Martin Devlin.

"I've got no doubt he'll get better before the World Cup. Going way back to when he had the operation, we learnt that it would take 18 months to get back to the level he was….to get that full acceleration and power back.

"We're reasonably happy. At the end of the day he was pretty solid through the tail end of the Super season.

"Like the rest of the Crusaders, he had four days preparation before playing South Africa, which is not the ideal thing to do.

"He's okay and building nicely."

Foster hinted the All Blacks would continue to hone their tactics right up to the World Cup quarter final in Japan.

"Our mind set is we've still got four weeks over there when we can grow our game…keep refining what we're doing," he said

"It's not like you want to go there and show everything on the table. The key is to peak at the right time."