Injured NZ fly-half Carter sidelined for up to month

The 31-year-old Carter would have been a nailed-on starter for the tournament opener against Australia in Sydney on Saturday, but is expected to be sidelined for three to four weeks, All Blacks coach Steve Hansen said at training.

"He was a bit sore after training so we got a scan and unfortunately he's damaged his calf," Hansen said in Porirua, near Wellington.

"It's disappointing for Dan ... It's not a biggie. It's just something that is a nuisance more than anything else."

Carter will miss the return match against the Wallabies at Eden Park on August 25 and would be scrambling to be fit for the All Blacks' third fixture against Argentina in Wellington on September 8.

The strain in Carter's left calf was a recurrence of an old injury, Hansen added.